From 3e29f34a4eef29f5b159749ccb1efb8867b2e651 Mon Sep 17 00:00:00 2001 From: "Maciej W. Rozycki" Date: Fri, 12 Dec 2014 13:31:53 +0000 Subject: [PATCH] MIPS: Keep the ISA bit in compressed code addresses 1. Background information The MIPS architecture, as originally designed and implemented in mid-1980s has a uniform instruction word size that is 4 bytes, naturally aligned. As such all MIPS instructions are located at addresses that have their bits #1 and #0 set to zeroes, and any attempt to execute an instruction from an address that has any of the two bits set to one causes an address error exception. This may for example happen when a jump-register instruction is executed whose register value used as the jump target has any of these bits set. Then in mid 1990s LSI sought a way to improve code density for their TinyRISC family of MIPS cores and invented an alternatively encoded instruction set in a joint effort with MIPS Technologies (then a subsidiary of SGI). The new instruction set has been named the MIPS16 ASE (Application-Specific Extension) and uses a variable instruction word size, which is 2 bytes (as the name of the ASE suggests) for most, but there are a couple of exceptions that take 4 bytes, and then most of the 2-byte instructions can be treated with a 2-byte extension prefix to expand the range of the immediate operands used. As a result instructions are no longer 4-byte aligned, instead they are aligned to a multiple of 2. That left the bit #0 still unused for code references, be it for the standard MIPS (i.e. as originally invented) or for the MIPS16 instruction set, and based on that observation a clever trick was invented that on one hand allowed the processor to be seamlessly switched between the two instruction sets at any time at the run time while on the other avoided the introduction of any special control register to do that. So it is the bit #0 of the instruction address that was chosen as the selector and named the ISA bit. Any instruction executed at an even address is interpreted as a standard MIPS instruction (the address still has to have its bit #1 clear), any instruction executed at an odd address is interpreted as a MIPS16 instruction. To switch between modes ordinary jump instructions are used, such as used for function calls and returns, specifically the bit #0 of the source register used in jump-register instructions selects the execution (ISA) mode for the following piece of code to be interpreted in. Additionally new jump-immediate instructions were added that flipped the ISA bit to select the opposite mode upon execution. They were considered necessary to avoid the need to make register jumps in all cases as the original jump-immediate instructions provided no way to change the bit #0 at all. This was all important for cases where standard MIPS and MIPS16 code had to be mixed, either for compatibility with the existing binary code base or to access resources not reachable from MIPS16 code (the MIPS16 instruction set only provides access to general-purpose registers, and not for example floating-point unit registers or privileged coprocessor 0 registers) -- pieces of code in the opposite mode can be executed as ordinary subroutine calls. A similar approach has been more recently adopted for the MIPS16 replacement instruction set defined as the so called microMIPS ASE. This is another instruction set encoding introduced to the MIPS architecture. Just like the MIPS16 ASE, the microMIPS instruction set uses a variable-length encoding, where each instruction takes a multiple of 2 bytes. The ISA bit has been reused and for microMIPS-capable processors selects between the standard MIPS and the microMIPS mode instead. 2. Statement of the problem To put it shortly, MIPS16 and microMIPS code pointers used by GDB are different to these observed at the run time. This results in the same expressions being evaluated producing different results in GDB and in the program being debugged. Obviously it's the results obtained at the run time that are correct (they define how the program behaves) and therefore by definition the results obtained in GDB are incorrect. A bit longer description will record that obviously at the run time the ISA bit has to be set correctly (refer to background information above if unsure why so) or the program will not run as expected. This is recorded in all the executable file structures used at the run time: the dynamic symbol table (but not always the static one!), the GOT, and obviously in all the addresses embedded in code or data of the program itself, calculated by applying the appropriate relocations at the static link time. While a program is being processed by GDB, the ISA bit is stripped off from any code addresses, presumably to make them the same as the respective raw memory byte address used by the processor to access the instruction in the instruction fetch access cycle. This stripping is actually performed outside GDB proper, in BFD, specifically _bfd_mips_elf_symbol_processing (elfxx-mips.c, see the piece of code at the very bottom of that function, starting with an: "If this is an odd-valued function symbol, assume it's a MIPS16 or microMIPS one." comment). This function is also responsible for symbol table dumps made by `objdump' too, so you'll never see the ISA bit reported there by that tool, you need to use `readelf'. This is however unlike what is ever done at the run time, the ISA bit once present is never stripped off, for example a cast like this: (short *) main will not strip the ISA bit off and if the resulting pointer is intended to be used to access instructions as data, for example for software instruction decoding (like for fault recovery or emulation in a signal handler) or for self-modifying code then the bit still has to be stripped off by an explicit AND operation. This is probably best illustrated with a simple real program example. Let's consider the following simple program: $ cat foobar.c int __attribute__ ((mips16)) foo (void) { return 1; } int __attribute__ ((mips16)) bar (void) { return 2; } int __attribute__ ((nomips16)) foo32 (void) { return 3; } int (*foo32p) (void) = foo32; int (*foop) (void) = foo; int fooi = (int) foo; int main (void) { return foop (); } $ This is plain C with no odd tricks, except from the instruction mode attributes. They are not necessary to trigger this problem, I just put them here so that the program can be contained in a single source file and to make it obvious which function is MIPS16 code and which is not. Let's try it with Linux, so that everyone can repeat this experiment: $ mips-linux-gnu-gcc -mips16 -g -O2 -o foobar foobar.c $ Let's have a look at some interesting symbols: $ mips-linux-gnu-readelf -s foobar | egrep 'table|foo|bar' Symbol table '.dynsym' contains 7 entries: Symbol table '.symtab' contains 95 entries: 55: 00000000 0 FILE LOCAL DEFAULT ABS foobar.c 66: 0040068c 4 FUNC GLOBAL DEFAULT [MIPS16] 12 bar 68: 00410848 4 OBJECT GLOBAL DEFAULT 21 foo32p 70: 00410844 4 OBJECT GLOBAL DEFAULT 21 foop 78: 00400684 8 FUNC GLOBAL DEFAULT 12 foo32 80: 00400680 4 FUNC GLOBAL DEFAULT [MIPS16] 12 foo 88: 00410840 4 OBJECT GLOBAL DEFAULT 21 fooi $ Hmm, no sight of the ISA bit, but notice how foo and bar (but not foo32!) have been marked as MIPS16 functions (ELF symbol structure's `st_other' field is used for that). So let's try to run and poke at this program with GDB. I'll be using a native system for simplicity (I'll be using ellipses here and there to remove unrelated clutter): $ ./foobar $ echo $? 1 $ So far, so good. $ gdb ./foobar [...] (gdb) break main Breakpoint 1 at 0x400490: file foobar.c, line 23. (gdb) run Starting program: .../foobar Breakpoint 1, main () at foobar.c:23 23 return foop (); (gdb) Yay, it worked! OK, so let's poke at it: (gdb) print main $1 = {int (void)} 0x400490
(gdb) print foo32 $2 = {int (void)} 0x400684 (gdb) print foo32p $3 = (int (*)(void)) 0x400684 (gdb) print bar $4 = {int (void)} 0x40068c (gdb) print foo $5 = {int (void)} 0x400680 (gdb) print foop $6 = (int (*)(void)) 0x400681 (gdb) A-ha! Here's the difference and finally the ISA bit! (gdb) print /x fooi $7 = 0x400681 (gdb) p/x $pc p/x $pc $8 = 0x400491 (gdb) And here as well... (gdb) advance foo foo () at foobar.c:4 4 } (gdb) disassemble Dump of assembler code for function foo: 0x00400680 <+0>: jr ra 0x00400682 <+2>: li v0,1 End of assembler dump. (gdb) finish Run till exit from #0 foo () at foobar.c:4 main () at foobar.c:24 24 } Value returned is $9 = 1 (gdb) continue Continuing. [Inferior 1 (process 14103) exited with code 01] (gdb) So let's be a bit inquisitive... (gdb) run Starting program: .../foobar Breakpoint 1, main () at foobar.c:23 23 return foop (); (gdb) Actually we do not like to run foo here at all. Let's run bar instead! (gdb) set foop = bar (gdb) print foop $10 = (int (*)(void)) 0x40068c (gdb) Hmm, no ISA bit. Is it going to work? (gdb) advance bar bar () at foobar.c:9 9 } (gdb) p/x $pc $11 = 0x40068c (gdb) disassemble Dump of assembler code for function bar: => 0x0040068c <+0>: jr ra 0x0040068e <+2>: li v0,2 End of assembler dump. (gdb) finish Run till exit from #0 bar () at foobar.c:9 Program received signal SIGILL, Illegal instruction. bar () at foobar.c:9 9 } (gdb) Oops! (gdb) p/x $pc $12 = 0x40068c (gdb) We're still there! (gdb) continue Continuing. Program terminated with signal SIGILL, Illegal instruction. The program no longer exists. (gdb) So let's try something else: (gdb) run Starting program: .../foobar Breakpoint 1, main () at foobar.c:23 23 return foop (); (gdb) set foop = foo (gdb) advance foo foo () at foobar.c:4 4 } (gdb) disassemble Dump of assembler code for function foo: => 0x00400680 <+0>: jr ra 0x00400682 <+2>: li v0,1 End of assembler dump. (gdb) finish Run till exit from #0 foo () at foobar.c:4 Program received signal SIGILL, Illegal instruction. foo () at foobar.c:4 4 } (gdb) continue Continuing. Program terminated with signal SIGILL, Illegal instruction. The program no longer exists. (gdb) The same problem! (gdb) run Starting program: /net/build2-lucid-cs/scratch/macro/mips-linux-fsf-gcc/isa-bit/foobar Breakpoint 1, main () at foobar.c:23 23 return foop (); (gdb) set foop = foo32 (gdb) advance foo32 foo32 () at foobar.c:14 14 } (gdb) disassemble Dump of assembler code for function foo32: => 0x00400684 <+0>: jr ra 0x00400688 <+4>: li v0,3 End of assembler dump. (gdb) finish Run till exit from #0 foo32 () at foobar.c:14 main () at foobar.c:24 24 } Value returned is $14 = 3 (gdb) continue Continuing. [Inferior 1 (process 14113) exited with code 03] (gdb) That did work though, so it's the ISA bit only! (gdb) quit Enough! That's the tip of the iceberg only though. So let's rebuild the executable with some dynamic symbols: $ mips-linux-gnu-gcc -mips16 -Wl,--export-dynamic -g -O2 -o foobar-dyn foobar.c $ mips-linux-gnu-readelf -s foobar-dyn | egrep 'table|foo|bar' Symbol table '.dynsym' contains 32 entries: 6: 004009cd 4 FUNC GLOBAL DEFAULT 12 bar 8: 00410b88 4 OBJECT GLOBAL DEFAULT 21 foo32p 9: 00410b84 4 OBJECT GLOBAL DEFAULT 21 foop 15: 004009c4 8 FUNC GLOBAL DEFAULT 12 foo32 17: 004009c1 4 FUNC GLOBAL DEFAULT 12 foo 25: 00410b80 4 OBJECT GLOBAL DEFAULT 21 fooi Symbol table '.symtab' contains 95 entries: 55: 00000000 0 FILE LOCAL DEFAULT ABS foobar.c 69: 004009cd 4 FUNC GLOBAL DEFAULT 12 bar 71: 00410b88 4 OBJECT GLOBAL DEFAULT 21 foo32p 72: 00410b84 4 OBJECT GLOBAL DEFAULT 21 foop 79: 004009c4 8 FUNC GLOBAL DEFAULT 12 foo32 81: 004009c1 4 FUNC GLOBAL DEFAULT 12 foo 89: 00410b80 4 OBJECT GLOBAL DEFAULT 21 fooi $ OK, now the ISA bit is there for a change, but the MIPS16 `st_other' attribute gone, hmm... What does `objdump' do then: $ mips-linux-gnu-objdump -Tt foobar-dyn | egrep 'SYMBOL|foo|bar' foobar-dyn: file format elf32-tradbigmips SYMBOL TABLE: 00000000 l df *ABS* 00000000 foobar.c 004009cc g F .text 00000004 0xf0 bar 00410b88 g O .data 00000004 foo32p 00410b84 g O .data 00000004 foop 004009c4 g F .text 00000008 foo32 004009c0 g F .text 00000004 0xf0 foo 00410b80 g O .data 00000004 fooi DYNAMIC SYMBOL TABLE: 004009cc g DF .text 00000004 Base 0xf0 bar 00410b88 g DO .data 00000004 Base foo32p 00410b84 g DO .data 00000004 Base foop 004009c4 g DF .text 00000008 Base foo32 004009c0 g DF .text 00000004 Base 0xf0 foo 00410b80 g DO .data 00000004 Base fooi $ Hmm, the attribute (0xf0, printed raw) is back, and the ISA bit gone again. Let's have a look at some DWARF-2 records GDB uses (I'll be stripping off a lot here for brevity) -- debug info: $ mips-linux-gnu-readelf -wi foobar Contents of the .debug_info section: [...] Compilation Unit @ offset 0x88: Length: 0xbb (32-bit) Version: 4 Abbrev Offset: 62 Pointer Size: 4 <0><93>: Abbrev Number: 1 (DW_TAG_compile_unit) <94> DW_AT_producer : (indirect string, offset: 0x19e): GNU C 4.8.0 20120513 (experimental) -meb -mips16 -march=mips32r2 -mhard-float -mllsc -mplt -mno-synci -mno-shared -mabi=32 -g -O2 <98> DW_AT_language : 1 (ANSI C) <99> DW_AT_name : (indirect string, offset: 0x190): foobar.c <9d> DW_AT_comp_dir : (indirect string, offset: 0x225): [...] DW_AT_ranges : 0x0 DW_AT_low_pc : 0x0 DW_AT_stmt_list : 0x27 <1>: Abbrev Number: 2 (DW_TAG_subprogram) DW_AT_external : 1 DW_AT_name : foo DW_AT_decl_file : 1 DW_AT_decl_line : 1 DW_AT_prototyped : 1 DW_AT_type : <0xc2> DW_AT_low_pc : 0x400680 DW_AT_high_pc : 0x400684 DW_AT_frame_base : 1 byte block: 9c (DW_OP_call_frame_cfa) DW_AT_GNU_all_call_sites: 1 <1>: Abbrev Number: 3 (DW_TAG_base_type) DW_AT_byte_size : 4 DW_AT_encoding : 5 (signed) DW_AT_name : int <1>: Abbrev Number: 4 (DW_TAG_subprogram) DW_AT_external : 1 DW_AT_name : (indirect string, offset: 0x18a): foo32 DW_AT_decl_file : 1 DW_AT_decl_line : 11 DW_AT_prototyped : 1 DW_AT_type : <0xc2> DW_AT_low_pc : 0x400684 DW_AT_high_pc : 0x40068c DW_AT_frame_base : 1 byte block: 9c (DW_OP_call_frame_cfa) DW_AT_GNU_all_call_sites: 1 <1>: Abbrev Number: 2 (DW_TAG_subprogram) DW_AT_external : 1 DW_AT_name : bar DW_AT_decl_file : 1 DW_AT_decl_line : 6 DW_AT_prototyped : 1 DW_AT_type : <0xc2> DW_AT_low_pc : 0x40068c DW_AT_high_pc : 0x400690 DW_AT_frame_base : 1 byte block: 9c (DW_OP_call_frame_cfa) DW_AT_GNU_all_call_sites: 1 <1>: Abbrev Number: 5 (DW_TAG_subprogram) DW_AT_external : 1 DW_AT_name : (indirect string, offset: 0x199): main DW_AT_decl_file : 1 DW_AT_decl_line : 21 DW_AT_prototyped : 1 DW_AT_type : <0xc2> DW_AT_low_pc : 0x400490 <102> DW_AT_high_pc : 0x4004a4 <106> DW_AT_frame_base : 1 byte block: 9c (DW_OP_call_frame_cfa) <108> DW_AT_GNU_all_tail_call_sites: 1 [...] $ -- no sign of the ISA bit anywhere -- frame info: $ mips-linux-gnu-readelf -wf foobar [...] Contents of the .debug_frame section: 00000000 0000000c ffffffff CIE Version: 1 Augmentation: "" Code alignment factor: 1 Data alignment factor: -4 Return address column: 31 DW_CFA_def_cfa_register: r29 DW_CFA_nop 00000010 0000000c 00000000 FDE cie=00000000 pc=00400680..00400684 00000020 0000000c 00000000 FDE cie=00000000 pc=00400684..0040068c 00000030 0000000c 00000000 FDE cie=00000000 pc=0040068c..00400690 00000040 00000018 00000000 FDE cie=00000000 pc=00400490..004004a4 DW_CFA_advance_loc: 6 to 00400496 DW_CFA_def_cfa_offset: 32 DW_CFA_offset: r31 at cfa-4 DW_CFA_advance_loc: 6 to 0040049c DW_CFA_restore: r31 DW_CFA_def_cfa_offset: 0 DW_CFA_nop DW_CFA_nop DW_CFA_nop [...] $ -- no sign of the ISA bit anywhere -- range info (GDB doesn't use arange): $ mips-linux-gnu-readelf -wR foobar Contents of the .debug_ranges section: Offset Begin End 00000000 00400680 00400690 00000000 00400490 004004a4 00000000 $ -- no sign of the ISA bit anywhere -- line info: $ mips-linux-gnu-readelf -wl foobar Raw dump of debug contents of section .debug_line: [...] Offset: 0x27 Length: 78 DWARF Version: 2 Prologue Length: 31 Minimum Instruction Length: 1 Initial value of 'is_stmt': 1 Line Base: -5 Line Range: 14 Opcode Base: 13 Opcodes: Opcode 1 has 0 args Opcode 2 has 1 args Opcode 3 has 1 args Opcode 4 has 1 args Opcode 5 has 1 args Opcode 6 has 0 args Opcode 7 has 0 args Opcode 8 has 0 args Opcode 9 has 1 args Opcode 10 has 0 args Opcode 11 has 0 args Opcode 12 has 1 args The Directory Table is empty. The File Name Table: Entry Dir Time Size Name 1 0 0 0 foobar.c Line Number Statements: Extended opcode 2: set Address to 0x400681 Special opcode 6: advance Address by 0 to 0x400681 and Line by 1 to 2 Special opcode 7: advance Address by 0 to 0x400681 and Line by 2 to 4 Special opcode 55: advance Address by 3 to 0x400684 and Line by 8 to 12 Special opcode 7: advance Address by 0 to 0x400684 and Line by 2 to 14 Advance Line by -7 to 7 Special opcode 131: advance Address by 9 to 0x40068d and Line by 0 to 7 Special opcode 7: advance Address by 0 to 0x40068d and Line by 2 to 9 Advance PC by 3 to 0x400690 Extended opcode 1: End of Sequence Extended opcode 2: set Address to 0x400491 Advance Line by 21 to 22 Copy Special opcode 6: advance Address by 0 to 0x400491 and Line by 1 to 23 Special opcode 60: advance Address by 4 to 0x400495 and Line by -1 to 22 Special opcode 34: advance Address by 2 to 0x400497 and Line by 1 to 23 Special opcode 62: advance Address by 4 to 0x40049b and Line by 1 to 24 Special opcode 32: advance Address by 2 to 0x40049d and Line by -1 to 23 Special opcode 6: advance Address by 0 to 0x40049d and Line by 1 to 24 Advance PC by 7 to 0x4004a4 Extended opcode 1: End of Sequence [...] -- a-ha, the ISA bit is there! However it's not always right for some reason, I don't have a small test case to show it, but here's an excerpt from MIPS16 libc, a prologue of a function: 00019630 <__libc_init_first>: 19630: e8a0 jrc ra 19632: 6500 nop 00019634 <_init>: 19634: f000 6a11 li v0,17 19638: f7d8 0b08 la v1,15e00 <_DYNAMIC+0x15c54> 1963c: f400 3240 sll v0,16 19640: e269 addu v0,v1 19642: 659a move gp,v0 19644: 64f6 save 48,ra,s0-s1 19646: 671c move s0,gp 19648: d204 sw v0,16(sp) 1964a: f352 984c lw v0,-27828(s0) 1964e: 6724 move s1,a0 and the corresponding DWARF-2 line info: Line Number Statements: Extended opcode 2: set Address to 0x19631 Advance Line by 44 to 45 Copy Special opcode 8: advance Address by 0 to 0x19631 and Line by 3 to 48 Special opcode 66: advance Address by 4 to 0x19635 and Line by 5 to 53 Advance PC by constant 17 to 0x19646 Special opcode 25: advance Address by 1 to 0x19647 and Line by 6 to 59 Advance Line by -6 to 53 Special opcode 33: advance Address by 2 to 0x19649 and Line by 0 to 53 Special opcode 39: advance Address by 2 to 0x1964b and Line by 6 to 59 Advance Line by -6 to 53 Special opcode 61: advance Address by 4 to 0x1964f and Line by 0 to 53 -- see that "Advance PC by constant 17" there? It clears the ISA bit, however code at 0x19646 is not standard MIPS code at all. For some reason the constant is always 17, I've never seen DW_LNS_const_add_pc used with any other value -- is that a binutils bug or what? 3. Solution: I think we should retain the value of the ISA bit in code references, that is effectively treat them as cookies as they indeed are (although trivially calculated) rather than raw memory byte addresses. In a perfect world both the static symbol table and the respective DWARF-2 records should be fixed to include the ISA bit in all the cases. I think however that this is infeasible. All the uses of `_bfd_mips_elf_symbol_processing' can not necessarily be tracked down. This function is used by `elf_slurp_symbol_table' that in turn is used by `bfd_canonicalize_symtab' and `bfd_canonicalize_dynamic_symtab', which are public interfaces. Similarly DWARF-2 records are used outside GDB, one notable if a bit questionable is the exception unwinder (libgcc/unwind-dw2.c) -- I have identified at least bits in `execute_cfa_program' and `uw_frame_state_for', both around the calls to `_Unwind_IsSignalFrame', that would need an update as they effectively flip the ISA bit freely; see also the comment about MASK_RETURN_ADDR in gcc/config/mips/mips.h. But there may be more places. Any change in how DWARF-2 records are produced would require an update there and would cause compatibility problems with libgcc.a binaries already distributed; given that this is a static library a complex change involving function renames would likely be required. I propose therefore to accept the existing inconsistencies and deal with them entirely within GDB. I have figured out that the ISA bit lost in various places can still be recovered as long as we have symbol information -- that'll have the `st_other' attribute correctly set to one of standard MIPS/MIPS16/microMIPS encoding. Here's the resulting change. It adds a couple of new `gdbarch' hooks, one to update symbol information with the ISA bit lost in `_bfd_mips_elf_symbol_processing', and two other ones to adjust DWARF-2 records as they're processed. The ISA bit is set in each address handled according to information retrieved from the symbol table for the symbol spanning the address if any; limits are adjusted based on the address they point to related to the respective base address. Additionally minimal symbol information has to be adjusted accordingly in its gdbarch hook. With these changes in place some complications with ISA bit juggling in the PC that never fully worked can be removed from the MIPS backend. Conversely, the generic dynamic linker event special breakpoint symbol handler has to be updated to call the minimal symbol gdbarch hook to record that the symbol is a MIPS16 or microMIPS address if applicable or the breakpoint will be set at the wrong address and either fail to work or cause SIGTRAPs (this is because the symbol is handled early on and bypasses regular symbol processing). 4. Results obtained The change fixes the example above -- to repeat only the crucial steps: (gdb) break main Breakpoint 1 at 0x400491: file foobar.c, line 23. (gdb) run Starting program: .../foobar Breakpoint 1, main () at foobar.c:23 23 return foop (); (gdb) print foo $1 = {int (void)} 0x400681 (gdb) set foop = bar (gdb) advance bar bar () at foobar.c:9 9 } (gdb) disassemble Dump of assembler code for function bar: => 0x0040068d <+0>: jr ra 0x0040068f <+2>: li v0,2 End of assembler dump. (gdb) finish Run till exit from #0 bar () at foobar.c:9 main () at foobar.c:24 24 } Value returned is $2 = 2 (gdb) continue Continuing. [Inferior 1 (process 14128) exited with code 02] (gdb) -- excellent! The change removes about 90 failures per MIPS16 multilib in mips-sde-elf testing too, results for MIPS16 are now similar to that for standard MIPS; microMIPS results are a bit worse because of host-I/O problems in QEMU used instead of MIPSsim for microMIPS testing only: === gdb Summary === # of expected passes 14299 # of unexpected failures 187 # of expected failures 56 # of known failures 58 # of unresolved testcases 11 # of untested testcases 52 # of unsupported tests 174 MIPS16: === gdb Summary === # of expected passes 14298 # of unexpected failures 187 # of unexpected successes 2 # of expected failures 54 # of known failures 58 # of unresolved testcases 12 # of untested testcases 52 # of unsupported tests 174 microMIPS: === gdb Summary === # of expected passes 14149 # of unexpected failures 201 # of unexpected successes 2 # of expected failures 54 # of known failures 58 # of unresolved testcases 7 # of untested testcases 53 # of unsupported tests 175 2014-12-12 Maciej W. Rozycki Maciej W. Rozycki Pedro Alves gdb/ * gdbarch.sh (elf_make_msymbol_special): Change type to `F', remove `predefault' and `invalid_p' initializers. (make_symbol_special): New architecture method. (adjust_dwarf2_addr, adjust_dwarf2_line): Likewise. (objfile, symbol): New declarations. * arch-utils.h (default_elf_make_msymbol_special): Remove prototype. (default_make_symbol_special): New prototype. (default_adjust_dwarf2_addr): Likewise. (default_adjust_dwarf2_line): Likewise. * mips-tdep.h (mips_unmake_compact_addr): New prototype. * arch-utils.c (default_elf_make_msymbol_special): Remove function. (default_make_symbol_special): New function. (default_adjust_dwarf2_addr): Likewise. (default_adjust_dwarf2_line): Likewise. * dwarf2-frame.c (decode_frame_entry_1): Call `gdbarch_adjust_dwarf2_addr'. * dwarf2loc.c (dwarf2_find_location_expression): Likewise. * dwarf2read.c (create_addrmap_from_index): Likewise. (process_psymtab_comp_unit_reader): Likewise. (add_partial_symbol): Likewise. (add_partial_subprogram): Likewise. (process_full_comp_unit): Likewise. (read_file_scope): Likewise. (read_func_scope): Likewise. Call `gdbarch_make_symbol_special'. (read_lexical_block_scope): Call `gdbarch_adjust_dwarf2_addr'. (read_call_site_scope): Likewise. (dwarf2_ranges_read): Likewise. (dwarf2_record_block_ranges): Likewise. (read_attribute_value): Likewise. (dwarf_decode_lines_1): Call `gdbarch_adjust_dwarf2_line'. (new_symbol_full): Call `gdbarch_adjust_dwarf2_addr'. * elfread.c (elf_symtab_read): Don't call `gdbarch_elf_make_msymbol_special' if unset. * mips-linux-tdep.c (micromips_linux_sigframe_validate): Strip the ISA bit from the PC. * mips-tdep.c (mips_unmake_compact_addr): New function. (mips_elf_make_msymbol_special): Set the ISA bit in the symbol's address appropriately. (mips_make_symbol_special): New function. (mips_pc_is_mips): Set the ISA bit before symbol lookup. (mips_pc_is_mips16): Likewise. (mips_pc_is_micromips): Likewise. (mips_pc_isa): Likewise. (mips_adjust_dwarf2_addr): New function. (mips_adjust_dwarf2_line): Likewise. (mips_read_pc, mips_unwind_pc): Keep the ISA bit. (mips_addr_bits_remove): Likewise. (mips_skip_trampoline_code): Likewise. (mips_write_pc): Don't set the ISA bit. (mips_eabi_push_dummy_call): Likewise. (mips_o64_push_dummy_call): Likewise. (mips_gdbarch_init): Install `mips_make_symbol_special', `mips_adjust_dwarf2_addr' and `mips_adjust_dwarf2_line' gdbarch handlers. * solib.c (gdb_bfd_lookup_symbol_from_symtab): Get target-specific symbol address adjustments. * gdbarch.h: Regenerate. * gdbarch.c: Regenerate. 2014-12-12 Maciej W. Rozycki gdb/testsuite/ * gdb.base/func-ptrs.c: New file. * gdb.base/func-ptrs.exp: New file. --- gdb/ChangeLog | 65 +++++++++ gdb/arch-utils.c | 23 +++- gdb/arch-utils.h | 17 ++- gdb/dwarf2-frame.c | 9 +- gdb/dwarf2loc.c | 3 + gdb/dwarf2read.c | 143 ++++++++++++++------ gdb/elfread.c | 12 +- gdb/gdbarch.c | 82 ++++++++++- gdb/gdbarch.h | 51 +++++++ gdb/gdbarch.sh | 38 +++++- gdb/mips-linux-tdep.c | 8 +- gdb/mips-tdep.c | 194 +++++++++++++++++---------- gdb/mips-tdep.h | 3 + gdb/solib.c | 22 ++- gdb/testsuite/ChangeLog | 5 + gdb/testsuite/gdb.base/func-ptrs.c | 50 +++++++ gdb/testsuite/gdb.base/func-ptrs.exp | 95 +++++++++++++ 17 files changed, 687 insertions(+), 133 deletions(-) create mode 100644 gdb/testsuite/gdb.base/func-ptrs.c create mode 100644 gdb/testsuite/gdb.base/func-ptrs.exp diff --git a/gdb/ChangeLog b/gdb/ChangeLog index bf1f80b58b6..1dc180a6f92 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,68 @@ +2014-12-12 Maciej W. Rozycki + Maciej W. Rozycki + Pedro Alves + + * gdbarch.sh (elf_make_msymbol_special): Change type to `F', + remove `predefault' and `invalid_p' initializers. + (make_symbol_special): New architecture method. + (adjust_dwarf2_addr, adjust_dwarf2_line): Likewise. + (objfile, symbol): New declarations. + * arch-utils.h (default_elf_make_msymbol_special): Remove + prototype. + (default_make_symbol_special): New prototype. + (default_adjust_dwarf2_addr): Likewise. + (default_adjust_dwarf2_line): Likewise. + * mips-tdep.h (mips_unmake_compact_addr): New prototype. + * arch-utils.c (default_elf_make_msymbol_special): Remove + function. + (default_make_symbol_special): New function. + (default_adjust_dwarf2_addr): Likewise. + (default_adjust_dwarf2_line): Likewise. + * dwarf2-frame.c (decode_frame_entry_1): Call + `gdbarch_adjust_dwarf2_addr'. + * dwarf2loc.c (dwarf2_find_location_expression): Likewise. + * dwarf2read.c (create_addrmap_from_index): Likewise. + (process_psymtab_comp_unit_reader): Likewise. + (add_partial_symbol): Likewise. + (add_partial_subprogram): Likewise. + (process_full_comp_unit): Likewise. + (read_file_scope): Likewise. + (read_func_scope): Likewise. Call `gdbarch_make_symbol_special'. + (read_lexical_block_scope): Call `gdbarch_adjust_dwarf2_addr'. + (read_call_site_scope): Likewise. + (dwarf2_ranges_read): Likewise. + (dwarf2_record_block_ranges): Likewise. + (read_attribute_value): Likewise. + (dwarf_decode_lines_1): Call `gdbarch_adjust_dwarf2_line'. + (new_symbol_full): Call `gdbarch_adjust_dwarf2_addr'. + * elfread.c (elf_symtab_read): Don't call + `gdbarch_elf_make_msymbol_special' if unset. + * mips-linux-tdep.c (micromips_linux_sigframe_validate): Strip + the ISA bit from the PC. + * mips-tdep.c (mips_unmake_compact_addr): New function. + (mips_elf_make_msymbol_special): Set the ISA bit in the symbol's + address appropriately. + (mips_make_symbol_special): New function. + (mips_pc_is_mips): Set the ISA bit before symbol lookup. + (mips_pc_is_mips16): Likewise. + (mips_pc_is_micromips): Likewise. + (mips_pc_isa): Likewise. + (mips_adjust_dwarf2_addr): New function. + (mips_adjust_dwarf2_line): Likewise. + (mips_read_pc, mips_unwind_pc): Keep the ISA bit. + (mips_addr_bits_remove): Likewise. + (mips_skip_trampoline_code): Likewise. + (mips_write_pc): Don't set the ISA bit. + (mips_eabi_push_dummy_call): Likewise. + (mips_o64_push_dummy_call): Likewise. + (mips_gdbarch_init): Install `mips_make_symbol_special', + `mips_adjust_dwarf2_addr' and `mips_adjust_dwarf2_line' gdbarch + handlers. + * solib.c (gdb_bfd_lookup_symbol_from_symtab): Get + target-specific symbol address adjustments. + * gdbarch.h: Regenerate. + * gdbarch.c: Regenerate. + 2014-12-12 Yao Qi PR tdep/14261 diff --git a/gdb/arch-utils.c b/gdb/arch-utils.c index a2e76deb876..33d5543101c 100644 --- a/gdb/arch-utils.c +++ b/gdb/arch-utils.c @@ -31,6 +31,7 @@ #include "target-descriptions.h" #include "objfiles.h" #include "language.h" +#include "symtab.h" #include "version.h" @@ -167,17 +168,35 @@ no_op_reg_to_regnum (struct gdbarch *gdbarch, int reg) } void -default_elf_make_msymbol_special (asymbol *sym, struct minimal_symbol *msym) +default_coff_make_msymbol_special (int val, struct minimal_symbol *msym) { return; } +/* See arch-utils.h. */ + void -default_coff_make_msymbol_special (int val, struct minimal_symbol *msym) +default_make_symbol_special (struct symbol *sym, struct objfile *objfile) { return; } +/* See arch-utils.h. */ + +CORE_ADDR +default_adjust_dwarf2_addr (CORE_ADDR pc) +{ + return pc; +} + +/* See arch-utils.h. */ + +CORE_ADDR +default_adjust_dwarf2_line (CORE_ADDR addr, int rel) +{ + return addr; +} + int cannot_register_not (struct gdbarch *gdbarch, int regnum) { diff --git a/gdb/arch-utils.h b/gdb/arch-utils.h index 1f5dd55f46a..11e68e27877 100644 --- a/gdb/arch-utils.h +++ b/gdb/arch-utils.h @@ -68,15 +68,22 @@ extern gdbarch_convert_from_func_ptr_addr_ftype convert_from_func_ptr_addr_ident extern int no_op_reg_to_regnum (struct gdbarch *gdbarch, int reg); -/* Do nothing version of elf_make_msymbol_special. */ - -void default_elf_make_msymbol_special (asymbol *sym, - struct minimal_symbol *msym); - /* Do nothing version of coff_make_msymbol_special. */ void default_coff_make_msymbol_special (int val, struct minimal_symbol *msym); +/* Do nothing default implementation of gdbarch_make_symbol_special. */ + +void default_make_symbol_special (struct symbol *sym, struct objfile *objfile); + +/* Do nothing default implementation of gdbarch_adjust_dwarf2_addr. */ + +CORE_ADDR default_adjust_dwarf2_addr (CORE_ADDR pc); + +/* Do nothing default implementation of gdbarch_adjust_dwarf2_line. */ + +CORE_ADDR default_adjust_dwarf2_line (CORE_ADDR addr, int rel); + /* Version of cannot_fetch_register() / cannot_store_register() that always fails. */ diff --git a/gdb/dwarf2-frame.c b/gdb/dwarf2-frame.c index 586f1345c1b..8747f4cc6b9 100644 --- a/gdb/dwarf2-frame.c +++ b/gdb/dwarf2-frame.c @@ -2066,6 +2066,7 @@ decode_frame_entry_1 (struct comp_unit *unit, const gdb_byte *start, { /* This is a FDE. */ struct dwarf2_fde *fde; + CORE_ADDR addr; /* Check that an FDE was expected. */ if ((entry_type & EH_FDE_TYPE_ID) == 0) @@ -2099,14 +2100,16 @@ decode_frame_entry_1 (struct comp_unit *unit, const gdb_byte *start, gdb_assert (fde->cie != NULL); - fde->initial_location = - read_encoded_value (unit, fde->cie->encoding, fde->cie->ptr_size, - buf, &bytes_read, 0); + addr = read_encoded_value (unit, fde->cie->encoding, fde->cie->ptr_size, + buf, &bytes_read, 0); + fde->initial_location = gdbarch_adjust_dwarf2_addr (gdbarch, addr); buf += bytes_read; fde->address_range = read_encoded_value (unit, fde->cie->encoding & 0x0f, fde->cie->ptr_size, buf, &bytes_read, 0); + addr = gdbarch_adjust_dwarf2_addr (gdbarch, addr + fde->address_range); + fde->address_range = addr - fde->initial_location; buf += bytes_read; /* A 'z' augmentation in the CIE implies the presence of an diff --git a/gdb/dwarf2loc.c b/gdb/dwarf2loc.c index 6e461bcdccf..fbaa7d30aac 100644 --- a/gdb/dwarf2loc.c +++ b/gdb/dwarf2loc.c @@ -4296,6 +4296,9 @@ loclist_describe_location (struct symbol *symbol, CORE_ADDR addr, low += base_address; high += base_address; + low = gdbarch_adjust_dwarf2_addr (gdbarch, low); + high = gdbarch_adjust_dwarf2_addr (gdbarch, high); + length = extract_unsigned_integer (loc_ptr, 2, byte_order); loc_ptr += 2; diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c index 829611dfe9d..e36af5ab43b 100644 --- a/gdb/dwarf2read.c +++ b/gdb/dwarf2read.c @@ -2824,6 +2824,7 @@ create_signatured_type_table_from_index (struct objfile *objfile, static void create_addrmap_from_index (struct objfile *objfile, struct mapped_index *index) { + struct gdbarch *gdbarch = get_objfile_arch (objfile); const gdb_byte *iter, *end; struct obstack temp_obstack; struct addrmap *mutable_map; @@ -2865,8 +2866,9 @@ create_addrmap_from_index (struct objfile *objfile, struct mapped_index *index) continue; } - addrmap_set_empty (mutable_map, lo + baseaddr, hi + baseaddr - 1, - dw2_get_cutu (cu_index)); + lo = gdbarch_adjust_dwarf2_addr (gdbarch, lo + baseaddr); + hi = gdbarch_adjust_dwarf2_addr (gdbarch, hi + baseaddr); + addrmap_set_empty (mutable_map, lo, hi - 1, dw2_get_cutu (cu_index)); } objfile->psymtabs_addrmap = addrmap_create_fixed (mutable_map, @@ -5849,6 +5851,7 @@ process_psymtab_comp_unit_reader (const struct die_reader_specs *reader, { struct dwarf2_cu *cu = reader->cu; struct objfile *objfile = cu->objfile; + struct gdbarch *gdbarch = get_objfile_arch (objfile); struct dwarf2_per_cu_data *per_cu = cu->per_cu; struct attribute *attr; CORE_ADDR baseaddr; @@ -5893,8 +5896,11 @@ process_psymtab_comp_unit_reader (const struct die_reader_specs *reader, /* Store the contiguous range if it is not empty; it can be empty for CUs with no code. */ addrmap_set_empty (objfile->psymtabs_addrmap, - best_lowpc + baseaddr, - best_highpc + baseaddr - 1, pst); + gdbarch_adjust_dwarf2_addr (gdbarch, + best_lowpc + baseaddr), + gdbarch_adjust_dwarf2_addr (gdbarch, + best_highpc + baseaddr) - 1, + pst); /* Check if comp unit has_children. If so, read the rest of the partial symbols from this comp unit. @@ -5925,8 +5931,8 @@ process_psymtab_comp_unit_reader (const struct die_reader_specs *reader, best_highpc = highpc; } } - pst->textlow = best_lowpc + baseaddr; - pst->texthigh = best_highpc + baseaddr; + pst->textlow = gdbarch_adjust_dwarf2_addr (gdbarch, best_lowpc + baseaddr); + pst->texthigh = gdbarch_adjust_dwarf2_addr (gdbarch, best_highpc + baseaddr); pst->n_global_syms = objfile->global_psymbols.next - (objfile->global_psymbols.list + pst->globals_offset); @@ -6789,6 +6795,7 @@ static void add_partial_symbol (struct partial_die_info *pdi, struct dwarf2_cu *cu) { struct objfile *objfile = cu->objfile; + struct gdbarch *gdbarch = get_objfile_arch (objfile); CORE_ADDR addr = 0; const char *actual_name = NULL; CORE_ADDR baseaddr; @@ -6806,31 +6813,30 @@ add_partial_symbol (struct partial_die_info *pdi, struct dwarf2_cu *cu) switch (pdi->tag) { case DW_TAG_subprogram: + addr = gdbarch_adjust_dwarf2_addr (gdbarch, pdi->lowpc + baseaddr); if (pdi->is_external || cu->language == language_ada) { /* brobecker/2007-12-26: Normally, only "external" DIEs are part of the global scope. But in Ada, we want to be able to access nested procedures globally. So all Ada subprograms are stored in the global scope. */ - /* prim_record_minimal_symbol (actual_name, pdi->lowpc + baseaddr, - mst_text, objfile); */ + /* prim_record_minimal_symbol (actual_name, addr, mst_text, + objfile); */ add_psymbol_to_list (actual_name, strlen (actual_name), built_actual_name != NULL, VAR_DOMAIN, LOC_BLOCK, &objfile->global_psymbols, - 0, pdi->lowpc + baseaddr, - cu->language, objfile); + 0, addr, cu->language, objfile); } else { - /* prim_record_minimal_symbol (actual_name, pdi->lowpc + baseaddr, - mst_file_text, objfile); */ + /* prim_record_minimal_symbol (actual_name, addr, mst_file_text, + objfile); */ add_psymbol_to_list (actual_name, strlen (actual_name), built_actual_name != NULL, VAR_DOMAIN, LOC_BLOCK, &objfile->static_psymbols, - 0, pdi->lowpc + baseaddr, - cu->language, objfile); + 0, addr, cu->language, objfile); } break; case DW_TAG_constant: @@ -7031,14 +7037,19 @@ add_partial_subprogram (struct partial_die_info *pdi, *highpc = pdi->highpc; if (set_addrmap) { - CORE_ADDR baseaddr; struct objfile *objfile = cu->objfile; + struct gdbarch *gdbarch = get_objfile_arch (objfile); + CORE_ADDR baseaddr; + CORE_ADDR highpc; + CORE_ADDR lowpc; baseaddr = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile)); - addrmap_set_empty (objfile->psymtabs_addrmap, - pdi->lowpc + baseaddr, - pdi->highpc - 1 + baseaddr, + lowpc = gdbarch_adjust_dwarf2_addr (gdbarch, + pdi->lowpc + baseaddr); + highpc = gdbarch_adjust_dwarf2_addr (gdbarch, + pdi->highpc + baseaddr); + addrmap_set_empty (objfile->psymtabs_addrmap, lowpc, highpc - 1, cu->per_cu->v.psymtab); } } @@ -7925,11 +7936,13 @@ process_full_comp_unit (struct dwarf2_per_cu_data *per_cu, { struct dwarf2_cu *cu = per_cu->cu; struct objfile *objfile = per_cu->objfile; + struct gdbarch *gdbarch = get_objfile_arch (objfile); CORE_ADDR lowpc, highpc; struct compunit_symtab *cust; struct cleanup *back_to, *delayed_list_cleanup; CORE_ADDR baseaddr; struct block *static_block; + CORE_ADDR addr; baseaddr = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile)); @@ -7960,8 +7973,8 @@ process_full_comp_unit (struct dwarf2_per_cu_data *per_cu, it, by scanning the DIE's below the compilation unit. */ get_scope_pc_bounds (cu->dies, &lowpc, &highpc, cu); - static_block - = end_symtab_get_static_block (highpc + baseaddr, 0, 1); + addr = gdbarch_adjust_dwarf2_addr (gdbarch, highpc + baseaddr); + static_block = end_symtab_get_static_block (addr, 0, 1); /* If the comp unit has DW_AT_ranges, it may have discontiguous ranges. Also, DW_AT_ranges may record ranges not belonging to any child DIEs @@ -9006,6 +9019,7 @@ static void read_file_scope (struct die_info *die, struct dwarf2_cu *cu) { struct objfile *objfile = dwarf2_per_objfile->objfile; + struct gdbarch *gdbarch = get_objfile_arch (objfile); struct cleanup *back_to = make_cleanup (null_cleanup, 0); CORE_ADDR lowpc = ((CORE_ADDR) -1); CORE_ADDR highpc = ((CORE_ADDR) 0); @@ -9024,8 +9038,7 @@ read_file_scope (struct die_info *die, struct dwarf2_cu *cu) from finish_block. */ if (lowpc == ((CORE_ADDR) -1)) lowpc = highpc; - lowpc += baseaddr; - highpc += baseaddr; + lowpc = gdbarch_adjust_dwarf2_addr (gdbarch, lowpc + baseaddr); find_file_and_directory (die, cu, &name, &comp_dir); @@ -11133,6 +11146,7 @@ static void read_func_scope (struct die_info *die, struct dwarf2_cu *cu) { struct objfile *objfile = cu->objfile; + struct gdbarch *gdbarch = get_objfile_arch (objfile); struct context_stack *new; CORE_ADDR lowpc; CORE_ADDR highpc; @@ -11185,8 +11199,8 @@ read_func_scope (struct die_info *die, struct dwarf2_cu *cu) return; } - lowpc += baseaddr; - highpc += baseaddr; + lowpc = gdbarch_adjust_dwarf2_addr (gdbarch, lowpc + baseaddr); + highpc = gdbarch_adjust_dwarf2_addr (gdbarch, highpc + baseaddr); /* If we have any template arguments, then we must allocate a different sort of symbol. */ @@ -11273,6 +11287,8 @@ read_func_scope (struct die_info *die, struct dwarf2_cu *cu) /* If we have address ranges, record them. */ dwarf2_record_block_ranges (die, block, baseaddr, cu); + gdbarch_make_symbol_special (gdbarch, new->name, objfile); + /* Attach template arguments to function. */ if (! VEC_empty (symbolp, template_args)) { @@ -11309,6 +11325,7 @@ static void read_lexical_block_scope (struct die_info *die, struct dwarf2_cu *cu) { struct objfile *objfile = cu->objfile; + struct gdbarch *gdbarch = get_objfile_arch (objfile); struct context_stack *new; CORE_ADDR lowpc, highpc; struct die_info *child_die; @@ -11323,8 +11340,8 @@ read_lexical_block_scope (struct die_info *die, struct dwarf2_cu *cu) describe ranges. */ if (!dwarf2_get_pc_bounds (die, &lowpc, &highpc, cu, NULL)) return; - lowpc += baseaddr; - highpc += baseaddr; + lowpc = gdbarch_adjust_dwarf2_addr (gdbarch, lowpc + baseaddr); + highpc = gdbarch_adjust_dwarf2_addr (gdbarch, highpc + baseaddr); push_context (0, lowpc); if (die->child != NULL) @@ -11386,6 +11403,7 @@ read_call_site_scope (struct die_info *die, struct dwarf2_cu *cu) return; } pc = attr_value_as_address (attr) + baseaddr; + pc = gdbarch_adjust_dwarf2_addr (gdbarch, pc); if (cu->call_site_htab == NULL) cu->call_site_htab = htab_create_alloc_ex (16, core_addr_hash, core_addr_eq, @@ -11534,7 +11552,10 @@ read_call_site_scope (struct die_info *die, struct dwarf2_cu *cu) "low pc, for referencing DIE 0x%x [in module %s]"), die->offset.sect_off, objfile_name (objfile)); else - SET_FIELD_PHYSADDR (call_site->target, lowpc + baseaddr); + { + lowpc = gdbarch_adjust_dwarf2_addr (gdbarch, lowpc + baseaddr); + SET_FIELD_PHYSADDR (call_site->target, lowpc); + } } } else @@ -11662,6 +11683,7 @@ dwarf2_ranges_read (unsigned offset, CORE_ADDR *low_return, struct partial_symtab *ranges_pst) { struct objfile *objfile = cu->objfile; + struct gdbarch *gdbarch = get_objfile_arch (objfile); struct comp_unit_head *cu_header = &cu->header; bfd *obfd = objfile->obfd; unsigned int addr_size = cu_header->addr_size; @@ -11769,10 +11791,17 @@ dwarf2_ranges_read (unsigned offset, CORE_ADDR *low_return, } if (ranges_pst != NULL) - addrmap_set_empty (objfile->psymtabs_addrmap, - range_beginning + baseaddr, - range_end - 1 + baseaddr, - ranges_pst); + { + CORE_ADDR lowpc; + CORE_ADDR highpc; + + lowpc = gdbarch_adjust_dwarf2_addr (gdbarch, + range_beginning + baseaddr); + highpc = gdbarch_adjust_dwarf2_addr (gdbarch, + range_end + baseaddr); + addrmap_set_empty (objfile->psymtabs_addrmap, lowpc, highpc - 1, + ranges_pst); + } /* FIXME: This is recording everything as a low-high segment of consecutive addresses. We should have a @@ -11986,6 +12015,7 @@ dwarf2_record_block_ranges (struct die_info *die, struct block *block, CORE_ADDR baseaddr, struct dwarf2_cu *cu) { struct objfile *objfile = cu->objfile; + struct gdbarch *gdbarch = get_objfile_arch (objfile); struct attribute *attr; struct attribute *attr_high; @@ -12001,7 +12031,9 @@ dwarf2_record_block_ranges (struct die_info *die, struct block *block, if (cu->header.version >= 4 && attr_form_is_constant (attr_high)) high += low; - record_block_range (block, baseaddr + low, baseaddr + high - 1); + low = gdbarch_adjust_dwarf2_addr (gdbarch, low + baseaddr); + high = gdbarch_adjust_dwarf2_addr (gdbarch, high + baseaddr); + record_block_range (block, low, high - 1); } } @@ -12105,6 +12137,8 @@ dwarf2_record_block_ranges (struct die_info *die, struct block *block, continue; } + start = gdbarch_adjust_dwarf2_addr (gdbarch, start); + end = gdbarch_adjust_dwarf2_addr (gdbarch, end); record_block_range (block, start, end - 1); } } @@ -15931,6 +15965,8 @@ read_attribute_value (const struct die_reader_specs *reader, const gdb_byte *info_ptr) { struct dwarf2_cu *cu = reader->cu; + struct objfile *objfile = cu->objfile; + struct gdbarch *gdbarch = get_objfile_arch (objfile); bfd *abfd = reader->abfd; struct comp_unit_head *cu_header = &cu->header; unsigned int bytes_read; @@ -15953,6 +15989,7 @@ read_attribute_value (const struct die_reader_specs *reader, break; case DW_FORM_addr: DW_ADDR (attr) = read_address (abfd, info_ptr, cu, &bytes_read); + DW_ADDR (attr) = gdbarch_adjust_dwarf2_addr (gdbarch, DW_ADDR (attr)); info_ptr += bytes_read; break; case DW_FORM_block2: @@ -17284,8 +17321,12 @@ dwarf_decode_lines_1 (struct line_header *lh, struct dwarf2_cu *cu, /* Read the statement sequences until there's nothing left. */ while (line_ptr < line_end) { - /* state machine registers */ - CORE_ADDR address = 0; + /* State machine registers. Call `gdbarch_adjust_dwarf2_line' + on the initial 0 address as if there was a line entry for it + so that the backend has a chance to adjust it and also record + it in case it needs it. This is currently used by MIPS code, + cf. `mips_adjust_dwarf2_line'. */ + CORE_ADDR address = gdbarch_adjust_dwarf2_line (gdbarch, 0, 0); unsigned int file = 1; unsigned int line = 1; int is_stmt = lh->default_is_stmt; @@ -17328,12 +17369,14 @@ dwarf_decode_lines_1 (struct line_header *lh, struct dwarf2_cu *cu, { /* Special opcode. */ unsigned char adj_opcode; + CORE_ADDR addr_adj; int line_delta; adj_opcode = op_code - lh->opcode_base; - address += (((op_index + (adj_opcode / lh->line_range)) + addr_adj = (((op_index + (adj_opcode / lh->line_range)) / lh->maximum_ops_per_instruction) * lh->minimum_instruction_length); + address += gdbarch_adjust_dwarf2_line (gdbarch, addr_adj, 1); op_index = ((op_index + (adj_opcode / lh->line_range)) % lh->maximum_ops_per_instruction); line_delta = lh->line_base + (adj_opcode % lh->line_range); @@ -17410,6 +17453,7 @@ dwarf_decode_lines_1 (struct line_header *lh, struct dwarf2_cu *cu, op_index = 0; line_ptr += bytes_read; address += baseaddr; + address = gdbarch_adjust_dwarf2_line (gdbarch, address, 0); break; case DW_LNE_define_file: { @@ -17487,10 +17531,12 @@ dwarf_decode_lines_1 (struct line_header *lh, struct dwarf2_cu *cu, { CORE_ADDR adjust = read_unsigned_leb128 (abfd, line_ptr, &bytes_read); + CORE_ADDR addr_adj; - address += (((op_index + adjust) + addr_adj = (((op_index + adjust) / lh->maximum_ops_per_instruction) * lh->minimum_instruction_length); + address += gdbarch_adjust_dwarf2_line (gdbarch, addr_adj, 1); op_index = ((op_index + adjust) % lh->maximum_ops_per_instruction); line_ptr += bytes_read; @@ -17550,18 +17596,25 @@ dwarf_decode_lines_1 (struct line_header *lh, struct dwarf2_cu *cu, case DW_LNS_const_add_pc: { CORE_ADDR adjust = (255 - lh->opcode_base) / lh->line_range; + CORE_ADDR addr_adj; - address += (((op_index + adjust) + addr_adj = (((op_index + adjust) / lh->maximum_ops_per_instruction) * lh->minimum_instruction_length); + address += gdbarch_adjust_dwarf2_line (gdbarch, addr_adj, 1); op_index = ((op_index + adjust) % lh->maximum_ops_per_instruction); } break; case DW_LNS_fixed_advance_pc: - address += read_2_bytes (abfd, line_ptr); - op_index = 0; - line_ptr += 2; + { + CORE_ADDR addr_adj; + + addr_adj = read_2_bytes (abfd, line_ptr); + address += gdbarch_adjust_dwarf2_line (gdbarch, addr_adj, 1); + op_index = 0; + line_ptr += 2; + } break; default: { @@ -17813,6 +17866,7 @@ new_symbol_full (struct die_info *die, struct type *type, struct dwarf2_cu *cu, struct symbol *space) { struct objfile *objfile = cu->objfile; + struct gdbarch *gdbarch = get_objfile_arch (objfile); struct symbol *sym = NULL; const char *name; struct attribute *attr = NULL; @@ -17890,8 +17944,13 @@ new_symbol_full (struct die_info *die, struct type *type, struct dwarf2_cu *cu, case DW_TAG_label: attr = dwarf2_attr (die, DW_AT_low_pc, cu); if (attr) - SYMBOL_VALUE_ADDRESS (sym) - = attr_value_as_address (attr) + baseaddr; + { + CORE_ADDR addr; + + addr = attr_value_as_address (attr); + addr = gdbarch_adjust_dwarf2_addr (gdbarch, addr + baseaddr); + SYMBOL_VALUE_ADDRESS (sym) = addr; + } SYMBOL_TYPE (sym) = objfile_type (objfile)->builtin_core_addr; SYMBOL_DOMAIN (sym) = LABEL_DOMAIN; SYMBOL_ACLASS_INDEX (sym) = LOC_LABEL; diff --git a/gdb/elfread.c b/gdb/elfread.c index 19aaed35dc8..b4ec0677770 100644 --- a/gdb/elfread.c +++ b/gdb/elfread.c @@ -247,6 +247,8 @@ elf_symtab_read (struct objfile *objfile, int type, const char *filesymname = ""; struct dbx_symfile_info *dbx = DBX_SYMFILE_INFO (objfile); int stripped = (bfd_get_symcount (objfile->obfd) == 0); + int elf_make_msymbol_special_p + = gdbarch_elf_make_msymbol_special_p (gdbarch); for (i = 0; i < number_of_symbols; i++) { @@ -330,7 +332,8 @@ elf_symtab_read (struct objfile *objfile, int type, if (msym != NULL) { msym->filename = filesymname; - gdbarch_elf_make_msymbol_special (gdbarch, sym, msym); + if (elf_make_msymbol_special_p) + gdbarch_elf_make_msymbol_special (gdbarch, sym, msym); } continue; } @@ -558,7 +561,8 @@ elf_symtab_read (struct objfile *objfile, int type, } msym->filename = filesymname; - gdbarch_elf_make_msymbol_special (gdbarch, sym, msym); + if (elf_make_msymbol_special_p) + gdbarch_elf_make_msymbol_special (gdbarch, sym, msym); } /* If we see a default versioned symbol, install it under @@ -597,7 +601,9 @@ elf_symtab_read (struct objfile *objfile, int type, SET_MSYMBOL_SIZE (mtramp, MSYMBOL_SIZE (msym)); mtramp->created_by_gdb = 1; mtramp->filename = filesymname; - gdbarch_elf_make_msymbol_special (gdbarch, sym, mtramp); + if (elf_make_msymbol_special_p) + gdbarch_elf_make_msymbol_special (gdbarch, + sym, mtramp); } } } diff --git a/gdb/gdbarch.c b/gdb/gdbarch.c index f89a6d2e0b2..132fff35289 100644 --- a/gdb/gdbarch.c +++ b/gdb/gdbarch.c @@ -252,6 +252,9 @@ struct gdbarch gdbarch_in_function_epilogue_p_ftype *in_function_epilogue_p; gdbarch_elf_make_msymbol_special_ftype *elf_make_msymbol_special; gdbarch_coff_make_msymbol_special_ftype *coff_make_msymbol_special; + gdbarch_make_symbol_special_ftype *make_symbol_special; + gdbarch_adjust_dwarf2_addr_ftype *adjust_dwarf2_addr; + gdbarch_adjust_dwarf2_line_ftype *adjust_dwarf2_line; int cannot_step_breakpoint; int have_nonsteppable_watchpoint; gdbarch_address_class_type_flags_ftype *address_class_type_flags; @@ -392,8 +395,10 @@ gdbarch_alloc (const struct gdbarch_info *info, gdbarch->skip_solib_resolver = generic_skip_solib_resolver; gdbarch->in_solib_return_trampoline = generic_in_solib_return_trampoline; gdbarch->in_function_epilogue_p = generic_in_function_epilogue_p; - gdbarch->elf_make_msymbol_special = default_elf_make_msymbol_special; gdbarch->coff_make_msymbol_special = default_coff_make_msymbol_special; + gdbarch->make_symbol_special = default_make_symbol_special; + gdbarch->adjust_dwarf2_addr = default_adjust_dwarf2_addr; + gdbarch->adjust_dwarf2_line = default_adjust_dwarf2_line; gdbarch->register_reggroup_p = default_register_reggroup_p; gdbarch->skip_permanent_breakpoint = default_skip_permanent_breakpoint; gdbarch->displaced_step_hw_singlestep = default_displaced_step_hw_singlestep; @@ -565,8 +570,11 @@ verify_gdbarch (struct gdbarch *gdbarch) /* Skip verify of skip_solib_resolver, invalid_p == 0 */ /* Skip verify of in_solib_return_trampoline, invalid_p == 0 */ /* Skip verify of in_function_epilogue_p, invalid_p == 0 */ - /* Skip verify of elf_make_msymbol_special, invalid_p == 0 */ + /* Skip verify of elf_make_msymbol_special, has predicate. */ /* Skip verify of coff_make_msymbol_special, invalid_p == 0 */ + /* Skip verify of make_symbol_special, invalid_p == 0 */ + /* Skip verify of adjust_dwarf2_addr, invalid_p == 0 */ + /* Skip verify of adjust_dwarf2_line, invalid_p == 0 */ /* Skip verify of cannot_step_breakpoint, invalid_p == 0 */ /* Skip verify of have_nonsteppable_watchpoint, invalid_p == 0 */ /* Skip verify of address_class_type_flags, has predicate. */ @@ -690,6 +698,12 @@ gdbarch_dump (struct gdbarch *gdbarch, struct ui_file *file) fprintf_unfiltered (file, "gdbarch_dump: adjust_breakpoint_address = <%s>\n", host_address_to_string (gdbarch->adjust_breakpoint_address)); + fprintf_unfiltered (file, + "gdbarch_dump: adjust_dwarf2_addr = <%s>\n", + host_address_to_string (gdbarch->adjust_dwarf2_addr)); + fprintf_unfiltered (file, + "gdbarch_dump: adjust_dwarf2_line = <%s>\n", + host_address_to_string (gdbarch->adjust_dwarf2_line)); fprintf_unfiltered (file, "gdbarch_dump: auto_charset = <%s>\n", host_address_to_string (gdbarch->auto_charset)); @@ -837,6 +851,9 @@ gdbarch_dump (struct gdbarch *gdbarch, struct ui_file *file) fprintf_unfiltered (file, "gdbarch_dump: ecoff_reg_to_regnum = <%s>\n", host_address_to_string (gdbarch->ecoff_reg_to_regnum)); + fprintf_unfiltered (file, + "gdbarch_dump: gdbarch_elf_make_msymbol_special_p() = %d\n", + gdbarch_elf_make_msymbol_special_p (gdbarch)); fprintf_unfiltered (file, "gdbarch_dump: elf_make_msymbol_special = <%s>\n", host_address_to_string (gdbarch->elf_make_msymbol_special)); @@ -1017,6 +1034,9 @@ gdbarch_dump (struct gdbarch *gdbarch, struct ui_file *file) fprintf_unfiltered (file, "gdbarch_dump: make_corefile_notes = <%s>\n", host_address_to_string (gdbarch->make_corefile_notes)); + fprintf_unfiltered (file, + "gdbarch_dump: make_symbol_special = <%s>\n", + host_address_to_string (gdbarch->make_symbol_special)); fprintf_unfiltered (file, "gdbarch_dump: gdbarch_max_insn_length_p() = %d\n", gdbarch_max_insn_length_p (gdbarch)); @@ -3065,6 +3085,13 @@ set_gdbarch_in_function_epilogue_p (struct gdbarch *gdbarch, gdbarch->in_function_epilogue_p = in_function_epilogue_p; } +int +gdbarch_elf_make_msymbol_special_p (struct gdbarch *gdbarch) +{ + gdb_assert (gdbarch != NULL); + return gdbarch->elf_make_msymbol_special != NULL; +} + void gdbarch_elf_make_msymbol_special (struct gdbarch *gdbarch, asymbol *sym, struct minimal_symbol *msym) { @@ -3099,6 +3126,57 @@ set_gdbarch_coff_make_msymbol_special (struct gdbarch *gdbarch, gdbarch->coff_make_msymbol_special = coff_make_msymbol_special; } +void +gdbarch_make_symbol_special (struct gdbarch *gdbarch, struct symbol *sym, struct objfile *objfile) +{ + gdb_assert (gdbarch != NULL); + gdb_assert (gdbarch->make_symbol_special != NULL); + if (gdbarch_debug >= 2) + fprintf_unfiltered (gdb_stdlog, "gdbarch_make_symbol_special called\n"); + gdbarch->make_symbol_special (sym, objfile); +} + +void +set_gdbarch_make_symbol_special (struct gdbarch *gdbarch, + gdbarch_make_symbol_special_ftype make_symbol_special) +{ + gdbarch->make_symbol_special = make_symbol_special; +} + +CORE_ADDR +gdbarch_adjust_dwarf2_addr (struct gdbarch *gdbarch, CORE_ADDR pc) +{ + gdb_assert (gdbarch != NULL); + gdb_assert (gdbarch->adjust_dwarf2_addr != NULL); + if (gdbarch_debug >= 2) + fprintf_unfiltered (gdb_stdlog, "gdbarch_adjust_dwarf2_addr called\n"); + return gdbarch->adjust_dwarf2_addr (pc); +} + +void +set_gdbarch_adjust_dwarf2_addr (struct gdbarch *gdbarch, + gdbarch_adjust_dwarf2_addr_ftype adjust_dwarf2_addr) +{ + gdbarch->adjust_dwarf2_addr = adjust_dwarf2_addr; +} + +CORE_ADDR +gdbarch_adjust_dwarf2_line (struct gdbarch *gdbarch, CORE_ADDR addr, int rel) +{ + gdb_assert (gdbarch != NULL); + gdb_assert (gdbarch->adjust_dwarf2_line != NULL); + if (gdbarch_debug >= 2) + fprintf_unfiltered (gdb_stdlog, "gdbarch_adjust_dwarf2_line called\n"); + return gdbarch->adjust_dwarf2_line (addr, rel); +} + +void +set_gdbarch_adjust_dwarf2_line (struct gdbarch *gdbarch, + gdbarch_adjust_dwarf2_line_ftype adjust_dwarf2_line) +{ + gdbarch->adjust_dwarf2_line = adjust_dwarf2_line; +} + int gdbarch_cannot_step_breakpoint (struct gdbarch *gdbarch) { diff --git a/gdb/gdbarch.h b/gdb/gdbarch.h index 0bd1d5662d8..ba4fe62ae94 100644 --- a/gdb/gdbarch.h +++ b/gdb/gdbarch.h @@ -51,6 +51,8 @@ struct target_ops; struct obstack; struct bp_target_info; struct target_desc; +struct objfile; +struct symbol; struct displaced_step_closure; struct core_regset_section; struct syscall; @@ -688,6 +690,16 @@ typedef int (gdbarch_in_function_epilogue_p_ftype) (struct gdbarch *gdbarch, COR extern int gdbarch_in_function_epilogue_p (struct gdbarch *gdbarch, CORE_ADDR addr); extern void set_gdbarch_in_function_epilogue_p (struct gdbarch *gdbarch, gdbarch_in_function_epilogue_p_ftype *in_function_epilogue_p); +/* Process an ELF symbol in the minimal symbol table in a backend-specific + way. Normally this hook is supposed to do nothing, however if required, + then this hook can be used to apply tranformations to symbols that are + considered special in some way. For example the MIPS backend uses it + to interpret `st_other' information to mark compressed code symbols so + that they can be treated in the appropriate manner in the processing of + the main symbol table and DWARF-2 records. */ + +extern int gdbarch_elf_make_msymbol_special_p (struct gdbarch *gdbarch); + typedef void (gdbarch_elf_make_msymbol_special_ftype) (asymbol *sym, struct minimal_symbol *msym); extern void gdbarch_elf_make_msymbol_special (struct gdbarch *gdbarch, asymbol *sym, struct minimal_symbol *msym); extern void set_gdbarch_elf_make_msymbol_special (struct gdbarch *gdbarch, gdbarch_elf_make_msymbol_special_ftype *elf_make_msymbol_special); @@ -696,6 +708,45 @@ typedef void (gdbarch_coff_make_msymbol_special_ftype) (int val, struct minimal_ extern void gdbarch_coff_make_msymbol_special (struct gdbarch *gdbarch, int val, struct minimal_symbol *msym); extern void set_gdbarch_coff_make_msymbol_special (struct gdbarch *gdbarch, gdbarch_coff_make_msymbol_special_ftype *coff_make_msymbol_special); +/* Process a symbol in the main symbol table in a backend-specific way. + Normally this hook is supposed to do nothing, however if required, + then this hook can be used to apply tranformations to symbols that + are considered special in some way. This is currently used by the + MIPS backend to make sure compressed code symbols have the ISA bit + set. This in turn is needed for symbol values seen in GDB to match + the values used at the runtime by the program itself, for function + and label references. */ + +typedef void (gdbarch_make_symbol_special_ftype) (struct symbol *sym, struct objfile *objfile); +extern void gdbarch_make_symbol_special (struct gdbarch *gdbarch, struct symbol *sym, struct objfile *objfile); +extern void set_gdbarch_make_symbol_special (struct gdbarch *gdbarch, gdbarch_make_symbol_special_ftype *make_symbol_special); + +/* Adjust the address retrieved from a DWARF-2 record other than a line + entry in a backend-specific way. Normally this hook is supposed to + return the address passed unchanged, however if that is incorrect for + any reason, then this hook can be used to fix the address up in the + required manner. This is currently used by the MIPS backend to make + sure addresses in FDE, range records, etc. referring to compressed + code have the ISA bit set, matching line information and the symbol + table. */ + +typedef CORE_ADDR (gdbarch_adjust_dwarf2_addr_ftype) (CORE_ADDR pc); +extern CORE_ADDR gdbarch_adjust_dwarf2_addr (struct gdbarch *gdbarch, CORE_ADDR pc); +extern void set_gdbarch_adjust_dwarf2_addr (struct gdbarch *gdbarch, gdbarch_adjust_dwarf2_addr_ftype *adjust_dwarf2_addr); + +/* Adjust the address updated by a line entry in a backend-specific way. + Normally this hook is supposed to return the address passed unchanged, + however in the case of inconsistencies in these records, this hook can + be used to fix them up in the required manner. This is currently used + by the MIPS backend to make sure all line addresses in compressed code + are presented with the ISA bit set, which is not always the case. This + in turn ensures breakpoint addresses are correctly matched against the + stop PC. */ + +typedef CORE_ADDR (gdbarch_adjust_dwarf2_line_ftype) (CORE_ADDR addr, int rel); +extern CORE_ADDR gdbarch_adjust_dwarf2_line (struct gdbarch *gdbarch, CORE_ADDR addr, int rel); +extern void set_gdbarch_adjust_dwarf2_line (struct gdbarch *gdbarch, gdbarch_adjust_dwarf2_line_ftype *adjust_dwarf2_line); + extern int gdbarch_cannot_step_breakpoint (struct gdbarch *gdbarch); extern void set_gdbarch_cannot_step_breakpoint (struct gdbarch *gdbarch, int cannot_step_breakpoint); diff --git a/gdb/gdbarch.sh b/gdb/gdbarch.sh index 8aeb394cbe2..25544e3d8d5 100755 --- a/gdb/gdbarch.sh +++ b/gdb/gdbarch.sh @@ -635,8 +635,42 @@ m:int:in_solib_return_trampoline:CORE_ADDR pc, const char *name:pc, name::generi # which don't suffer from that problem could just let this functionality # untouched. m:int:in_function_epilogue_p:CORE_ADDR addr:addr:0:generic_in_function_epilogue_p::0 -f:void:elf_make_msymbol_special:asymbol *sym, struct minimal_symbol *msym:sym, msym::default_elf_make_msymbol_special::0 +# Process an ELF symbol in the minimal symbol table in a backend-specific +# way. Normally this hook is supposed to do nothing, however if required, +# then this hook can be used to apply tranformations to symbols that are +# considered special in some way. For example the MIPS backend uses it +# to interpret \`st_other' information to mark compressed code symbols so +# that they can be treated in the appropriate manner in the processing of +# the main symbol table and DWARF-2 records. +F:void:elf_make_msymbol_special:asymbol *sym, struct minimal_symbol *msym:sym, msym f:void:coff_make_msymbol_special:int val, struct minimal_symbol *msym:val, msym::default_coff_make_msymbol_special::0 +# Process a symbol in the main symbol table in a backend-specific way. +# Normally this hook is supposed to do nothing, however if required, +# then this hook can be used to apply tranformations to symbols that +# are considered special in some way. This is currently used by the +# MIPS backend to make sure compressed code symbols have the ISA bit +# set. This in turn is needed for symbol values seen in GDB to match +# the values used at the runtime by the program itself, for function +# and label references. +f:void:make_symbol_special:struct symbol *sym, struct objfile *objfile:sym, objfile::default_make_symbol_special::0 +# Adjust the address retrieved from a DWARF-2 record other than a line +# entry in a backend-specific way. Normally this hook is supposed to +# return the address passed unchanged, however if that is incorrect for +# any reason, then this hook can be used to fix the address up in the +# required manner. This is currently used by the MIPS backend to make +# sure addresses in FDE, range records, etc. referring to compressed +# code have the ISA bit set, matching line information and the symbol +# table. +f:CORE_ADDR:adjust_dwarf2_addr:CORE_ADDR pc:pc::default_adjust_dwarf2_addr::0 +# Adjust the address updated by a line entry in a backend-specific way. +# Normally this hook is supposed to return the address passed unchanged, +# however in the case of inconsistencies in these records, this hook can +# be used to fix them up in the required manner. This is currently used +# by the MIPS backend to make sure all line addresses in compressed code +# are presented with the ISA bit set, which is not always the case. This +# in turn ensures breakpoint addresses are correctly matched against the +# stop PC. +f:CORE_ADDR:adjust_dwarf2_line:CORE_ADDR addr, int rel:addr, rel::default_adjust_dwarf2_line::0 v:int:cannot_step_breakpoint:::0:0::0 v:int:have_nonsteppable_watchpoint:::0:0::0 F:int:address_class_type_flags:int byte_size, int dwarf2_addr_class:byte_size, dwarf2_addr_class @@ -1153,6 +1187,8 @@ struct target_ops; struct obstack; struct bp_target_info; struct target_desc; +struct objfile; +struct symbol; struct displaced_step_closure; struct core_regset_section; struct syscall; diff --git a/gdb/mips-linux-tdep.c b/gdb/mips-linux-tdep.c index 41602ba7369..243a671212a 100644 --- a/gdb/mips-linux-tdep.c +++ b/gdb/mips-linux-tdep.c @@ -1364,7 +1364,13 @@ micromips_linux_sigframe_validate (const struct tramp_frame *self, struct frame_info *this_frame, CORE_ADDR *pc) { - return mips_pc_is_micromips (get_frame_arch (this_frame), *pc); + if (mips_pc_is_micromips (get_frame_arch (this_frame), *pc)) + { + *pc = mips_unmake_compact_addr (*pc); + return 1; + } + else + return 0; } /* Implement the "write_pc" gdbarch method. */ diff --git a/gdb/mips-tdep.c b/gdb/mips-tdep.c index c072bf0be67..5a5a7164336 100644 --- a/gdb/mips-tdep.c +++ b/gdb/mips-tdep.c @@ -340,6 +340,15 @@ make_compact_addr (CORE_ADDR addr) return ((addr) | (CORE_ADDR) 1); } +/* Extern version of unmake_compact_addr; we use a separate function + so that unmake_compact_addr can be inlined throughout this file. */ + +CORE_ADDR +mips_unmake_compact_addr (CORE_ADDR addr) +{ + return unmake_compact_addr (addr); +} + /* Functions for setting and testing a bit in a minimal symbol that marks it as MIPS16 or microMIPS function. The MSB of the minimal symbol's "info" field is used for this purpose. @@ -369,9 +378,15 @@ mips_elf_make_msymbol_special (asymbol * sym, struct minimal_symbol *msym) return; if (ELF_ST_IS_MICROMIPS (st_other)) - MSYMBOL_TARGET_FLAG_2 (msym) = 1; + { + MSYMBOL_TARGET_FLAG_2 (msym) = 1; + SET_MSYMBOL_VALUE_ADDRESS (msym, MSYMBOL_VALUE_RAW_ADDRESS (msym) | 1); + } else if (ELF_ST_IS_MIPS16 (st_other)) - MSYMBOL_TARGET_FLAG_1 (msym) = 1; + { + MSYMBOL_TARGET_FLAG_1 (msym) = 1; + SET_MSYMBOL_VALUE_ADDRESS (msym, MSYMBOL_VALUE_RAW_ADDRESS (msym) | 1); + } } /* Return one iff MSYM refers to standard ISA code. */ @@ -398,6 +413,35 @@ msymbol_is_micromips (struct minimal_symbol *msym) return MSYMBOL_TARGET_FLAG_2 (msym); } +/* Set the ISA bit in the main symbol too, complementing the corresponding + minimal symbol setting and reflecting the run-time value of the symbol. + The need for comes from the ISA bit having been cleared as code in + `_bfd_mips_elf_symbol_processing' separated it into the ELF symbol's + `st_other' STO_MIPS16 or STO_MICROMIPS annotation, making the values + of symbols referring to compressed code different in GDB to the values + used by actual code. That in turn makes them evaluate incorrectly in + expressions, producing results different to what the same expressions + yield when compiled into the program being debugged. */ + +static void +mips_make_symbol_special (struct symbol *sym, struct objfile *objfile) +{ + if (SYMBOL_CLASS (sym) == LOC_BLOCK) + { + /* We are in symbol reading so it is OK to cast away constness. */ + struct block *block = (struct block *) SYMBOL_BLOCK_VALUE (sym); + CORE_ADDR compact_block_start; + struct bound_minimal_symbol msym; + + compact_block_start = BLOCK_START (block) | 1; + msym = lookup_minimal_symbol_by_pc (compact_block_start); + if (msym.minsym && !msymbol_is_mips (msym.minsym)) + { + BLOCK_START (block) = compact_block_start; + } + } +} + /* XFER a value from the big/little/left end of the register. Depending on the size of the value it might occupy the entire register or just part of it. Make an allowance for this, aligning @@ -1132,7 +1176,7 @@ mips_pc_is_mips (CORE_ADDR memaddr) stored by elfread.c in the high bit of the info field. Use this to decide if the function is standard MIPS. Otherwise if bit 0 of the address is clear, then this is a standard MIPS function. */ - sym = lookup_minimal_symbol_by_pc (memaddr); + sym = lookup_minimal_symbol_by_pc (make_compact_addr (memaddr)); if (sym.minsym) return msymbol_is_mips (sym.minsym); else @@ -1150,7 +1194,7 @@ mips_pc_is_mips16 (struct gdbarch *gdbarch, CORE_ADDR memaddr) elfread.c in the high bit of the info field. Use this to decide if the function is MIPS16. Otherwise if bit 0 of the address is set, then ELF file flags will tell if this is a MIPS16 function. */ - sym = lookup_minimal_symbol_by_pc (memaddr); + sym = lookup_minimal_symbol_by_pc (make_compact_addr (memaddr)); if (sym.minsym) return msymbol_is_mips16 (sym.minsym); else @@ -1169,7 +1213,7 @@ mips_pc_is_micromips (struct gdbarch *gdbarch, CORE_ADDR memaddr) if the function is microMIPS. Otherwise if bit 0 of the address is set, then ELF file flags will tell if this is a microMIPS function. */ - sym = lookup_minimal_symbol_by_pc (memaddr); + sym = lookup_minimal_symbol_by_pc (make_compact_addr (memaddr)); if (sym.minsym) return msymbol_is_micromips (sym.minsym); else @@ -1189,7 +1233,7 @@ mips_pc_isa (struct gdbarch *gdbarch, CORE_ADDR memaddr) this to decide if the function is MIPS16 or microMIPS or normal MIPS. Otherwise if bit 0 of the address is set, then ELF file flags will tell if this is a MIPS16 or a microMIPS function. */ - sym = lookup_minimal_symbol_by_pc (memaddr); + sym = lookup_minimal_symbol_by_pc (make_compact_addr (memaddr)); if (sym.minsym) { if (msymbol_is_micromips (sym.minsym)) @@ -1210,6 +1254,67 @@ mips_pc_isa (struct gdbarch *gdbarch, CORE_ADDR memaddr) } } +/* Set the ISA bit correctly in the PC, used by DWARF-2 machinery. + The need for comes from the ISA bit having been cleared, making + addresses in FDE, range records, etc. referring to compressed code + different to those in line information, the symbol table and finally + the PC register. That in turn confuses many operations. */ + +static CORE_ADDR +mips_adjust_dwarf2_addr (CORE_ADDR pc) +{ + pc = unmake_compact_addr (pc); + return mips_pc_is_mips (pc) ? pc : make_compact_addr (pc); +} + +/* Recalculate the line record requested so that the resulting PC has + the ISA bit set correctly, used by DWARF-2 machinery. The need for + this adjustment comes from some records associated with compressed + code having the ISA bit cleared, most notably at function prologue + ends. The ISA bit is in this context retrieved from the minimal + symbol covering the address requested, which in turn has been + constructed from the binary's symbol table rather than DWARF-2 + information. The correct setting of the ISA bit is required for + breakpoint addresses to correctly match against the stop PC. + + As line entries can specify relative address adjustments we need to + keep track of the absolute value of the last line address recorded + in line information, so that we can calculate the actual address to + apply the ISA bit adjustment to. We use PC for this tracking and + keep the original address there. + + As such relative address adjustments can be odd within compressed + code we need to keep track of the last line address with the ISA + bit adjustment applied too, as the original address may or may not + have had the ISA bit set. We use ADJ_PC for this tracking and keep + the adjusted address there. + + For relative address adjustments we then use these variables to + calculate the address intended by line information, which will be + PC-relative, and return an updated adjustment carrying ISA bit + information, which will be ADJ_PC-relative. For absolute address + adjustments we just return the same address that we store in ADJ_PC + too. + + As the first line entry can be relative to an implied address value + of 0 we need to have the initial address set up that we store in PC + and ADJ_PC. This is arranged with a call from `dwarf_decode_lines_1' + that sets PC to 0 and ADJ_PC accordingly, usually 0 as well. */ + +static CORE_ADDR +mips_adjust_dwarf2_line (CORE_ADDR addr, int rel) +{ + static CORE_ADDR adj_pc; + static CORE_ADDR pc; + CORE_ADDR isa_pc; + + pc = rel ? pc + addr : addr; + isa_pc = mips_adjust_dwarf2_addr (pc); + addr = rel ? isa_pc - adj_pc : isa_pc; + adj_pc = isa_pc; + return addr; +} + /* Various MIPS16 thunk (aka stub or trampoline) names. */ static const char mips_str_mips16_call_stub[] = "__mips16_call_stub_"; @@ -1259,8 +1364,6 @@ mips_read_pc (struct regcache *regcache) LONGEST pc; regcache_cooked_read_signed (regcache, regnum, &pc); - if (is_compact_addr (pc)) - pc = unmake_compact_addr (pc); return pc; } @@ -1270,8 +1373,6 @@ mips_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame) CORE_ADDR pc; pc = frame_unwind_register_signed (next_frame, gdbarch_pc_regnum (gdbarch)); - if (is_compact_addr (pc)) - pc = unmake_compact_addr (pc); /* macro/2012-04-20: This hack skips over MIPS16 call thunks as intermediate frames. In this case we can get the caller's address from $ra, or if $ra contains an address within a thunk as well, then @@ -1281,15 +1382,9 @@ mips_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame) { pc = frame_unwind_register_signed (next_frame, gdbarch_num_regs (gdbarch) + MIPS_RA_REGNUM); - if (is_compact_addr (pc)) - pc = unmake_compact_addr (pc); if (mips_in_frame_stub (pc)) - { - pc = frame_unwind_register_signed - (next_frame, gdbarch_num_regs (gdbarch) + MIPS_S2_REGNUM); - if (is_compact_addr (pc)) - pc = unmake_compact_addr (pc); - } + pc = frame_unwind_register_signed + (next_frame, gdbarch_num_regs (gdbarch) + MIPS_S2_REGNUM); } return pc; } @@ -1323,10 +1418,7 @@ mips_write_pc (struct regcache *regcache, CORE_ADDR pc) { int regnum = gdbarch_pc_regnum (get_regcache_arch (regcache)); - if (mips_pc_is_mips (pc)) - regcache_cooked_write_unsigned (regcache, regnum, pc); - else - regcache_cooked_write_unsigned (regcache, regnum, make_compact_addr (pc)); + regcache_cooked_write_unsigned (regcache, regnum, pc); } /* Fetch and return instruction from the specified location. Handle @@ -3765,9 +3857,6 @@ mips_addr_bits_remove (struct gdbarch *gdbarch, CORE_ADDR addr) { struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); - if (is_compact_addr (addr)) - addr = unmake_compact_addr (addr); - if (mips_mask_address_p (tdep) && (((ULONGEST) addr) >> 32 == 0xffffffffUL)) /* This hack is a work-around for existing boards using PMON, the simulator, and any other 64-bit targets that doesn't have true @@ -4466,25 +4555,9 @@ mips_eabi_push_dummy_call (struct gdbarch *gdbarch, struct value *function, "mips_eabi_push_dummy_call: %d len=%d type=%d", argnum + 1, len, (int) typecode); - /* Function pointer arguments to mips16 code need to be made into - mips16 pointers. */ - if (typecode == TYPE_CODE_PTR - && TYPE_CODE (TYPE_TARGET_TYPE (arg_type)) == TYPE_CODE_FUNC) - { - CORE_ADDR addr = extract_signed_integer (value_contents (arg), - len, byte_order); - if (mips_pc_is_mips (addr)) - val = value_contents (arg); - else - { - store_signed_integer (valbuf, len, byte_order, - make_compact_addr (addr)); - val = valbuf; - } - } /* The EABI passes structures that do not fit in a register by reference. */ - else if (len > regsize + if (len > regsize && (typecode == TYPE_CODE_STRUCT || typecode == TYPE_CODE_UNION)) { store_unsigned_integer (valbuf, regsize, byte_order, @@ -5849,7 +5922,6 @@ mips_o64_push_dummy_call (struct gdbarch *gdbarch, struct value *function, for (argnum = 0; argnum < nargs; argnum++) { const gdb_byte *val; - gdb_byte valbuf[MAX_REGISTER_SIZE]; struct value *arg = args[argnum]; struct type *arg_type = check_typedef (value_type (arg)); int len = TYPE_LENGTH (arg_type); @@ -5862,21 +5934,6 @@ mips_o64_push_dummy_call (struct gdbarch *gdbarch, struct value *function, val = value_contents (arg); - /* Function pointer arguments to mips16 code need to be made into - mips16 pointers. */ - if (typecode == TYPE_CODE_PTR - && TYPE_CODE (TYPE_TARGET_TYPE (arg_type)) == TYPE_CODE_FUNC) - { - CORE_ADDR addr = extract_signed_integer (value_contents (arg), - len, byte_order); - if (!mips_pc_is_mips (addr)) - { - store_signed_integer (valbuf, len, byte_order, - make_compact_addr (addr)); - val = valbuf; - } - } - /* Floating point arguments passed in registers have to be treated specially. On 32-bit architectures, doubles are passed in register pairs; the even FP register gets the @@ -7833,27 +7890,15 @@ mips_skip_trampoline_code (struct frame_info *frame, CORE_ADDR pc) new_pc = mips_skip_mips16_trampoline_code (frame, pc); if (new_pc) - { - pc = new_pc; - if (is_compact_addr (pc)) - pc = unmake_compact_addr (pc); - } + pc = new_pc; new_pc = find_solib_trampoline_target (frame, pc); if (new_pc) - { - pc = new_pc; - if (is_compact_addr (pc)) - pc = unmake_compact_addr (pc); - } + pc = new_pc; new_pc = mips_skip_pic_trampoline_code (frame, pc); if (new_pc) - { - pc = new_pc; - if (is_compact_addr (pc)) - pc = unmake_compact_addr (pc); - } + pc = new_pc; } while (pc != target_pc); @@ -8509,6 +8554,9 @@ mips_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches) set_gdbarch_elf_make_msymbol_special (gdbarch, mips_elf_make_msymbol_special); + set_gdbarch_make_symbol_special (gdbarch, mips_make_symbol_special); + set_gdbarch_adjust_dwarf2_addr (gdbarch, mips_adjust_dwarf2_addr); + set_gdbarch_adjust_dwarf2_line (gdbarch, mips_adjust_dwarf2_line); regnum = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct mips_regnum); *regnum = mips_regnum; diff --git a/gdb/mips-tdep.h b/gdb/mips-tdep.h index ba299528ed3..b42f2d66dff 100644 --- a/gdb/mips-tdep.h +++ b/gdb/mips-tdep.h @@ -155,6 +155,9 @@ enum /* Single step based on where the current instruction will take us. */ extern int mips_software_single_step (struct frame_info *frame); +/* Strip the ISA (compression) bit off from ADDR. */ +extern CORE_ADDR mips_unmake_compact_addr (CORE_ADDR addr); + /* Tell if the program counter value in MEMADDR is in a standard MIPS function. */ extern int mips_pc_is_mips (bfd_vma memaddr); diff --git a/gdb/solib.c b/gdb/solib.c index ce9dc05f9ad..4b4386ccf2a 100644 --- a/gdb/solib.c +++ b/gdb/solib.c @@ -1443,8 +1443,28 @@ gdb_bfd_lookup_symbol_from_symtab (bfd *abfd, if (match_sym (sym, data)) { + struct gdbarch *gdbarch = target_gdbarch (); + symaddr = sym->value; + + /* Some ELF targets fiddle with addresses of symbols they + consider special. They use minimal symbols to do that + and this is needed for correct breakpoint placement, + but we do not have full data here to build a complete + minimal symbol, so just set the address and let the + targets cope with that. */ + if (bfd_get_flavour (abfd) == bfd_target_elf_flavour + && gdbarch_elf_make_msymbol_special_p (gdbarch)) + { + struct minimal_symbol msym; + + memset (&msym, 0, sizeof (msym)); + SET_MSYMBOL_VALUE_ADDRESS (&msym, symaddr); + gdbarch_elf_make_msymbol_special (gdbarch, sym, &msym); + symaddr = MSYMBOL_VALUE_RAW_ADDRESS (&msym); + } + /* BFD symbols are section relative. */ - symaddr = sym->value + sym->section->vma; + symaddr += sym->section->vma; break; } } diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog index 5ce30296a74..6e17360842f 100644 --- a/gdb/testsuite/ChangeLog +++ b/gdb/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2014-12-12 Maciej W. Rozycki + + * gdb.base/func-ptrs.c: New file. + * gdb.base/func-ptrs.exp: New file. + 2014-12-10 Simon Marchi PR breakpoints/17012 diff --git a/gdb/testsuite/gdb.base/func-ptrs.c b/gdb/testsuite/gdb.base/func-ptrs.c new file mode 100644 index 00000000000..ce36074c625 --- /dev/null +++ b/gdb/testsuite/gdb.base/func-ptrs.c @@ -0,0 +1,50 @@ +/* This testcase is part of GDB, the GNU debugger. + + Copyright 2014 Free Software Foundation, Inc. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . */ + +void +sentinel (void) +{ + return; +} + +int +incr (int i) +{ + sentinel (); + return i + 1; +} + +int +decr (int i) +{ + sentinel (); + return i - 1; +} + +int (*calc) (int) = incr; + +int +main (void) +{ + int i = -1; + + i = calc (i); + i = calc (i); + i = calc (i); + + return i; +} diff --git a/gdb/testsuite/gdb.base/func-ptrs.exp b/gdb/testsuite/gdb.base/func-ptrs.exp new file mode 100644 index 00000000000..c26eb9df5ce --- /dev/null +++ b/gdb/testsuite/gdb.base/func-ptrs.exp @@ -0,0 +1,95 @@ +# Copyright 2014 Free Software Foundation, Inc. + +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see . + +set testname func-ptrs +set srcfile ${testname}.c +if { [prepare_for_testing ${testname}.exp ${testname} ${srcfile}] } { + return -1 +} + +if { ![runto_main] } { + untested ${testname}.exp + return -1 +} + + +# First set our breakpoints. + +set fp_breakpoint_re \ + "Breakpoint $decimal at $hex: file .*${srcfile}, line $decimal\\." +gdb_test "break sentinel if calc == decr" \ + "${fp_breakpoint_re}" \ + "breakpoint at sentinel" +gdb_test "break incr" \ + "${fp_breakpoint_re}" \ + "breakpoint at incr" +gdb_test "break decr" \ + "${fp_breakpoint_re}" \ + "breakpoint at decr" + + +# Check if we run through to the breakpoint in incr. + +gdb_test "continue" \ + "Breakpoint $decimal, incr \\(i=-1\\)\[ \r\n\]+at .*${srcfile}:$decimal\[\r\n\]+.*" \ + "continue to incr, first time" + + +# Go back up, make sure the return value is 0. + +gdb_test "finish" \ + "Run till exit from #0 +incr \\(i=-1\\)\[ \r\n\]+at .*${srcfile}:$decimal\[\r\n\]+($hex in )?main \\(\\)\[ \r\n\]+at .*${srcfile}:$decimal\[\r\n\]+.*Value returned is \\$$decimal = 0" \ + "go back to main from incr, first time" + + +# Redirect calc and see if we run to the breakpoint in decr instead. + +gdb_test_no_output "set calc = decr" "set calc to decr" +gdb_test "continue" \ + "Breakpoint $decimal, decr \\(i=0\\)\[ \r\n\]+at .*${srcfile}:$decimal\[\r\n\]+.*" \ + "continue to decr" + + +# Go back up, check if we stop in sentinel instead. + +gdb_test "finish" \ + "Run till exit from #0 +decr \\(i=0\\)\[ \r\n\]+at .*${srcfile}:$decimal\[\r\n\]+Breakpoint $decimal, sentinel \\(\\)\[ \r\n\]+at .*${srcfile}:$decimal\[\r\n\]+.*" \ + "stop in sentinel" + + +# Go back all the way up to main, make sure the return value is -1. + +gdb_test_no_output "up-silently" "move up to decr" +gdb_test "finish" \ + "Run till exit from #1 +($hex in )?decr \\(i=0\\)\[ \r\n\]+at .*${srcfile}:$decimal\[\r\n\]+($hex in )?main \\(\\)\[ \r\n\]+at .*${srcfile}:$decimal\[\r\n\]+.*Value returned is \\$$decimal = -1" \ + "go back to main from decr" + + +# Reset calc and see if we run to the breakpoint in incr again. + +gdb_test_no_output "set calc = incr" "set calc to incr" +gdb_test "continue" \ + "Breakpoint $decimal, incr \\(i=-1\\)\[ \r\n\]+at .*${srcfile}:$decimal\[\r\n\]+.*" \ + "continue to incr, second time" + + +# Go back up again, make sure the return value is 0. + +gdb_test "finish" \ + "Run till exit from #0 +incr \\(i=-1\\)\[ \r\n\]+at .*${srcfile}:$decimal\[\r\n\]+($hex in )?main \\(\\)\[ \r\n\]+at .*${srcfile}:$decimal\[\r\n\]+.*Value returned is \\$$decimal = 0" \ + "go back to main from incr, second time" + + +# All done! -- 2.30.2