Optimize branches to non-weak symbols with visibility

Branches to global non-weak symbols defined in the same segment with
non-default visibility can be optimized the same way as branches to
local symbols.

gas/

	* config/tc-i386.c (elf_symbol_resolved_in_segment_p): New.
	(md_estimate_size_before_relax): Use it.

gas/testsuite/

	* gas/i386/i386.exp: Run relax-3 and x86-64-relax-2.
	* gas/i386/relax-3.d: New file.
	* gas/i386/relax-3.s: Likewise.
	* gas/i386/x86-64-relax-2.d: Likewise.

diff --git a/gas/ChangeLog b/gas/ChangeLog
index 7f42a641308d5bd0eb84710fccab823cf997fcf4..9758e72b605db67364209e4c2571c3dcd9815cce 100644 (file)
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,8 @@
+2015-05-07  H.J. Lu  <hongjiu.lu@intel.com>
+
+       * config/tc-i386.c (elf_symbol_resolved_in_segment_p): New.
+       (md_estimate_size_before_relax): Use it.
+
 2015-05-06  Jose E. Marchesi  <jose.marchesi@oracle.com>
 
        * config/tc-sparc.c: Typo in comment fixed.

diff --git a/gas/config/tc-i386.c b/gas/config/tc-i386.c
index 50f9cb47ea39cd03908658a51fbdc0b776825203..c4ba13dab4dbe47f9df505ec405bddb001261572 100644 (file)
--- a/gas/config/tc-i386.c
+++ b/gas/config/tc-i386.c
@@ -8772,6 +8772,25 @@ i386_frag_max_var (fragS *frag)
   return TYPE_FROM_RELAX_STATE (frag->fr_subtype) == UNCOND_JUMP ? 4 : 5;
 }
 
+#if defined (OBJ_ELF) || defined (OBJ_MAYBE_ELF)
+static int
+elf_symbol_resolved_in_segment_p (symbolS *fr_symbol)
+{
+  /* STT_GNU_IFUNC symbol must go through PLT.  */
+  if ((symbol_get_bfdsym (fr_symbol)->flags
+       & BSF_GNU_INDIRECT_FUNCTION) != 0)
+    return 0;
+
+  if (!S_IS_EXTERNAL (fr_symbol))
+    /* Symbol may be weak or local.  */
+    return !S_IS_WEAK (fr_symbol);
+
+  /* Global symbols with default visibility in a shared library may be
+     preempted by another definition.  */
+  return ELF_ST_VISIBILITY (S_GET_OTHER (fr_symbol)) != STV_DEFAULT;
+}
+#endif
+
 /* md_estimate_size_before_relax()
 
    Called just before relax() for rs_machine_dependent frags.  The x86
@@ -8795,10 +8814,7 @@ md_estimate_size_before_relax (fragS *fragP, segT segment)
   if (S_GET_SEGMENT (fragP->fr_symbol) != segment
 #if defined (OBJ_ELF) || defined (OBJ_MAYBE_ELF)
       || (IS_ELF
-         && (S_IS_EXTERNAL (fragP->fr_symbol)
-             || S_IS_WEAK (fragP->fr_symbol)
-             || ((symbol_get_bfdsym (fragP->fr_symbol)->flags
-                  & BSF_GNU_INDIRECT_FUNCTION))))
+         && !elf_symbol_resolved_in_segment_p (fragP->fr_symbol))
 #endif
 #if defined (OBJ_COFF) && defined (TE_PE)
       || (OUTPUT_FLAVOR == bfd_target_coff_flavour

diff --git a/gas/testsuite/ChangeLog b/gas/testsuite/ChangeLog
index 6339bff8640710fd718ea6c5ea4e4aecdfe44155..1cfa5772151d5bea818e85829ac4f1532906ca99 100644 (file)
--- a/gas/testsuite/ChangeLog
+++ b/gas/testsuite/ChangeLog
@@ -1,3 +1,10 @@
+2015-05-07  H.J. Lu  <hongjiu.lu@intel.com>
+
+       * gas/i386/i386.exp: Run relax-3 and x86-64-relax-2.
+       * gas/i386/relax-3.d: New file.
+       * gas/i386/relax-3.s: Likewise.
+       * gas/i386/x86-64-relax-2.d: Likewise.
+
 2015-05-06  Jose E. Marchesi  <jose.marchesi@oracle.com>
 
        * gas/sparc/natural-32.d: Test ldn, ldna, stn, stna, slln, srln,

diff --git a/gas/testsuite/gas/i386/i386.exp b/gas/testsuite/gas/i386/i386.exp
index e1fdd1822540baa8de75c3c8ecde56397c0dbc61..af56c263991753bfad640120d274cfe4f72ad98c 100644 (file)
--- a/gas/testsuite/gas/i386/i386.exp
+++ b/gas/testsuite/gas/i386/i386.exp
@@ -394,6 +394,8 @@ if [expr ([istarget "i*86-*-*"] ||  [istarget "x86_64-*-*"]) && [gas_32_check]]
        run_dump_test "size-4"
 
        run_dump_test "note"
+
+       run_dump_test "relax-3"
     }
 
     # This is a PE specific test.
@@ -748,6 +750,8 @@ if [expr ([istarget "i*86-*-*"] || [istarget "x86_64-*-*"]) && [gas_64_check]] t
        run_dump_test "x86-64-size-4"
        run_dump_test "x86-64-size-5"
        run_list_test "x86-64-size-inval-1" "-al"
+
+       run_dump_test "x86-64-relax-2"
     }
 
     set ASFLAGS "$old_ASFLAGS"

diff --git a/gas/testsuite/gas/i386/relax-3.d b/gas/testsuite/gas/i386/relax-3.d
new file mode 100644 (file)
index 0000000..8aa94e9
--- /dev/null
+++ b/gas/testsuite/gas/i386/relax-3.d
@@ -0,0 +1,30 @@
+#objdump: -dwr
+
+.*: +file format .*
+
+Disassembly of section .text:
+
+0+ <foo>:
+[      ]*[a-f0-9]+:    eb 1f                   jmp    21 <local>
+[      ]*[a-f0-9]+:    eb 19                   jmp    1d <hidden_def>
+[      ]*[a-f0-9]+:    e9 fc ff ff ff          jmp    5 <foo\+0x5>     5: (R_386_PC)?(DISP)?32 global_def
+[      ]*[a-f0-9]+:    e9 fc ff ff ff          jmp    a <foo\+0xa>     a: (R_386_PC)?(DISP)?32 weak_def
+[      ]*[a-f0-9]+:    e9 fc ff ff ff          jmp    f <foo\+0xf>     f: (R_386_PC)?(DISP)?32 weak_hidden_undef
+[      ]*[a-f0-9]+:    e9 fc ff ff ff          jmp    14 <foo\+0x14>   14: (R_386_PC)?(DISP)?32        weak_hidden_def
+[      ]*[a-f0-9]+:    e9 fc ff ff ff          jmp    19 <foo\+0x19>   19: (R_386_PC)?(DISP)?32        hidden_undef
+
+0+1d <hidden_def>:
+[      ]*[a-f0-9]+:    c3                      ret    
+
+0+1e <weak_hidden_def>:
+[      ]*[a-f0-9]+:    c3                      ret    
+
+0+1f <global_def>:
+[      ]*[a-f0-9]+:    c3                      ret    
+
+0+20 <weak_def>:
+[      ]*[a-f0-9]+:    c3                      ret    
+
+0+21 <local>:
+[      ]*[a-f0-9]+:    c3                      ret    
+#pass

diff --git a/gas/testsuite/gas/i386/relax-3.s b/gas/testsuite/gas/i386/relax-3.s
new file mode 100644 (file)
index 0000000..ab52185
--- /dev/null
+++ b/gas/testsuite/gas/i386/relax-3.s
@@ -0,0 +1,39 @@
+       .text
+       .global foo
+foo:
+       jmp local
+       jmp hidden_def
+       jmp global_def
+       jmp weak_def
+       jmp weak_hidden_undef
+       jmp weak_hidden_def
+       jmp hidden_undef
+
+       .hidden hidden_undef
+
+       .global hidden_def
+       .hidden hidden_def
+hidden_def:
+       ret
+
+       .global weak_hidden_def
+       .hidden weak_hidden_def
+       .weak weak_hidden_def
+weak_hidden_def:
+       ret
+
+       .global global_def
+global_def:
+       ret
+
+       .global weak_def
+       .weak weak_def
+weak_def:
+       ret
+
+local:
+       ret
+
+       .global weak_hidden_undef
+       .weak weak_hidden_undef
+       .hidden weak_hidden_undef

diff --git a/gas/testsuite/gas/i386/x86-64-relax-2.d b/gas/testsuite/gas/i386/x86-64-relax-2.d
new file mode 100644 (file)
index 0000000..7b0bd56
--- /dev/null
+++ b/gas/testsuite/gas/i386/x86-64-relax-2.d
@@ -0,0 +1,32 @@
+#source: relax-3.s
+#objdump: -dwr
+
+.*: +file format .*
+
+
+Disassembly of section .text:
+
+0+ <foo>:
+[      ]*[a-f0-9]+:    eb 1f                   jmp    21 <local>
+[      ]*[a-f0-9]+:    eb 19                   jmp    1d <hidden_def>
+[      ]*[a-f0-9]+:    e9 00 00 00 00          jmpq   9 <foo\+0x9>     5: R_X86_64_PC32        global_def-0x4
+[      ]*[a-f0-9]+:    e9 00 00 00 00          jmpq   e <foo\+0xe>     a: R_X86_64_PC32        weak_def-0x4
+[      ]*[a-f0-9]+:    e9 00 00 00 00          jmpq   13 <foo\+0x13>   f: R_X86_64_PC32        weak_hidden_undef-0x4
+[      ]*[a-f0-9]+:    e9 00 00 00 00          jmpq   18 <foo\+0x18>   14: R_X86_64_PC32       weak_hidden_def-0x4
+[      ]*[a-f0-9]+:    e9 00 00 00 00          jmpq   1d <hidden_def>  19: R_X86_64_PC32       hidden_undef-0x4
+
+0+1d <hidden_def>:
+[      ]*[a-f0-9]+:    c3                      retq   
+
+0+1e <weak_hidden_def>:
+[      ]*[a-f0-9]+:    c3                      retq   
+
+0+1f <global_def>:
+[      ]*[a-f0-9]+:    c3                      retq   
+
+0+20 <weak_def>:
+[      ]*[a-f0-9]+:    c3                      retq   
+
+0+21 <local>:
+[      ]*[a-f0-9]+:    c3                      retq   
+#pass