From a442cac5084e97d47223bac61cfc4d168c568ba4 Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Mon, 7 Jun 2021 08:49:33 +0200 Subject: [PATCH] ix86: wrap constants Non-64-bit code should get handled the same with or without BFD64. This wasn't the case though in a number of situations (and quite likely there are more that I haven't spotted yet). It's not very nice to tie the check in md_apply_fix() to object_64bit, but afaict at that time we have no record anymore of the mode an insn was assembled in (it might also have been data). This doesn't look to be the first inconsistency of this kind, though. In x86_cons() it's even less clear what the right approach would be: flag_code shouldn't matter for data emission, but instead we'd need to know from which mode(s) the data actually gets accessed. On this basis, signed_cons() also gets adjusted. --- gas/ChangeLog | 9 +++++ gas/config/tc-i386.c | 34 +++++++++++++--- gas/testsuite/gas/i386/i386.exp | 2 + gas/testsuite/gas/i386/wrap32-data.d | 23 +++++++++++ gas/testsuite/gas/i386/wrap32-text.d | 43 ++++++++++++++++++++ gas/testsuite/gas/i386/wrap32.s | 60 ++++++++++++++++++++++++++++ 6 files changed, 165 insertions(+), 6 deletions(-) create mode 100644 gas/testsuite/gas/i386/wrap32-data.d create mode 100644 gas/testsuite/gas/i386/wrap32-text.d create mode 100644 gas/testsuite/gas/i386/wrap32.s diff --git a/gas/ChangeLog b/gas/ChangeLog index 67b4583f212..b1d65569ce8 100644 --- a/gas/ChangeLog +++ b/gas/ChangeLog @@ -1,3 +1,12 @@ +2021-06-07 Jan Beulich + + * config/tc-i386.c (extend_to_32bit_address): New. + (x86_cons, i386_finalize_immediate, md_apply_fix): Use it. + (signed_cons): Use object_64bit. + * testsuite/gas/i386/wrap32.s, testsuite/gas/i386/wrap32-data.d, + testsuite/gas/i386/wrap32-text.d: New. + * testsuite/gas/i386/i386.exp: Run new tests. + 2021-06-03 Alan Modra PR 1202 diff --git a/gas/config/tc-i386.c b/gas/config/tc-i386.c index d3441988e34..a6bc597a354 100644 --- a/gas/config/tc-i386.c +++ b/gas/config/tc-i386.c @@ -2457,6 +2457,19 @@ fits_in_unsigned_long (addressT num ATTRIBUTE_UNUSED) #endif } /* fits_in_unsigned_long() */ +static INLINE valueT extend_to_32bit_address (addressT num) +{ +#ifdef BFD64 + if (fits_in_unsigned_long(num)) + return (num ^ ((addressT) 1 << 31)) - ((addressT) 1 << 31); + + if (!fits_in_signed_long (num)) + return num & 0xffffffff; +#endif + + return num; +} + static INLINE int fits_in_disp8 (offsetT num) { @@ -10457,13 +10470,17 @@ x86_cons (expressionS *exp, int size) if (intel_syntax) i386_intel_simplify (exp); + /* If not 64bit, massage value, to account for wraparound when !BFD64. */ + if (size == 4 && exp->X_op == O_constant && !object_64bit) + exp->X_add_number = extend_to_32bit_address (exp->X_add_number); + return got_reloc; } static void signed_cons (int size) { - if (flag_code == CODE_64BIT) + if (object_64bit) cons_sign = 1; cons (size); cons_sign = -1; @@ -10718,11 +10735,11 @@ i386_finalize_immediate (segT exp_seg ATTRIBUTE_UNUSED, expressionS *exp, { /* Size it properly later. */ i.types[this_operand].bitfield.imm64 = 1; - /* If not 64bit, sign extend val. */ - if (flag_code != CODE_64BIT - && (exp->X_add_number & ~(((addressT) 2 << 31) - 1)) == 0) - exp->X_add_number - = (exp->X_add_number ^ ((addressT) 1 << 31)) - ((addressT) 1 << 31); + + /* If not 64bit, sign/zero extend val, to account for wraparound + when !BFD64. */ + if (flag_code != CODE_64BIT) + exp->X_add_number = extend_to_32bit_address (exp->X_add_number); } #if (defined (OBJ_AOUT) || defined (OBJ_MAYBE_AOUT)) else if (OUTPUT_FLAVOR == bfd_target_aout_flavour @@ -12640,6 +12657,11 @@ md_apply_fix (fixS *fixP, valueT *valP, segT seg ATTRIBUTE_UNUSED) break; } #endif /* defined (OBJ_ELF) || defined (OBJ_MAYBE_ELF) */ + + /* If not 64bit, massage value, to account for wraparound when !BFD64. */ + if (!object_64bit) + value = extend_to_32bit_address (value); + *valP = value; #endif /* !defined (TE_Mach) */ diff --git a/gas/testsuite/gas/i386/i386.exp b/gas/testsuite/gas/i386/i386.exp index a459c6fe392..efcccafc034 100644 --- a/gas/testsuite/gas/i386/i386.exp +++ b/gas/testsuite/gas/i386/i386.exp @@ -148,6 +148,8 @@ if [gas_32_check] then { run_dump_test "addr32" run_dump_test "code16" run_list_test "oversized16" "-al" + run_dump_test "wrap32-text" + run_dump_test "wrap32-data" run_dump_test "sse4_1" run_dump_test "sse4_1-intel" run_dump_test "sse4_2" diff --git a/gas/testsuite/gas/i386/wrap32-data.d b/gas/testsuite/gas/i386/wrap32-data.d new file mode 100644 index 00000000000..bebec98933a --- /dev/null +++ b/gas/testsuite/gas/i386/wrap32-data.d @@ -0,0 +1,23 @@ +#name: i386 32-bit wrapping calculations (data/ELF) +#source: wrap32.s +#objdump: -rsj .data + +.*: +file format .* + +RELOCATION RECORDS FOR \[\.data\]: + +OFFSET +TYPE +VALUE * +0*10 (R_386_32|dir32) *sym +0*14 (R_386_32|dir32) *sym +0*18 (R_386_32|dir32) *sym +0*1c (R_386_32|dir32) *sym +0*30 (R_386_32|dir32) *sym +0*34 (R_386_32|dir32) *sym +0*38 (R_386_32|dir32) *sym +0*3c (R_386_32|dir32) *sym + +Contents of section .data: + 0+00 f4 ?00 ?00 ?00 f4 ?00 ?00 ?00 90 ?00 ?00 ?00 90 ?00 ?00 ?00 .* + 0+10 00 ?ff ?ff ?ff 00 ?ff ?ff ?ff f4 ?00 ?00 ?00 f4 ?00 ?00 ?00 .* + 0+20 f4 ?02 ?00 ?70 f4 ?00 ?00 ?80 90 ?02 ?00 ?70 90 ?00 ?00 ?80 .* + 0+30 00 ?01 ?00 ?70 00 ?ff ?ff ?7f f4 ?02 ?00 ?70 f4 ?00 ?00 ?80 .* diff --git a/gas/testsuite/gas/i386/wrap32-text.d b/gas/testsuite/gas/i386/wrap32-text.d new file mode 100644 index 00000000000..3ebbd8582e2 --- /dev/null +++ b/gas/testsuite/gas/i386/wrap32-text.d @@ -0,0 +1,43 @@ +#name: i386 32-bit wrapping calculations (text) +#source: wrap32.s +#objdump: -dwr + +.*: +file format .* + +Disassembly of section .text: + +0+ : +[ ]*[0-9a-f]+:[ ]+b8 f4 00 00 00 mov \$0xf4,%eax +[ ]*[0-9a-f]+:[ ]+ba f4 00 00 00 mov \$0xf4,%edx +[ ]*[0-9a-f]+:[ ]+b8 90 00 00 00 mov \$0x90,%eax +[ ]*[0-9a-f]+:[ ]+ba 90 00 00 00 mov \$0x90,%edx +[ ]*[0-9a-f]+:[ ]+b8 00 ff ff ff mov \$0xffffff00,%eax[ ]+[0-9a-f]+: (R_386_32|dir32)[ ]+sym +[ ]*[0-9a-f]+:[ ]+ba 00 ff ff ff mov \$0xffffff00,%edx[ ]+[0-9a-f]+: (R_386_32|dir32)[ ]+sym +[ ]*[0-9a-f]+:[ ]+b8 f4 00 00 00 mov \$0xf4,%eax[ ]+[0-9a-f]+: (R_386_32|dir32)[ ]+sym +[ ]*[0-9a-f]+:[ ]+ba f4 00 00 00 mov \$0xf4,%edx[ ]+[0-9a-f]+: (R_386_32|dir32)[ ]+sym +[ ]*[0-9a-f]+:[ ]+c7 00 f4 00 00 00 movl \$0xf4,\(%eax\) +[ ]*[0-9a-f]+:[ ]+c7 02 f4 00 00 00 movl \$0xf4,\(%edx\) +[ ]*[0-9a-f]+:[ ]+c7 00 90 00 00 00 movl \$0x90,\(%eax\) +[ ]*[0-9a-f]+:[ ]+c7 02 90 00 00 00 movl \$0x90,\(%edx\) +[ ]*[0-9a-f]+:[ ]+c7 00 00 ff ff ff movl \$0xffffff00,\(%eax\)[ ]+[0-9a-f]+: (R_386_32|dir32)[ ]+sym +[ ]*[0-9a-f]+:[ ]+c7 02 00 ff ff ff movl \$0xffffff00,\(%edx\)[ ]+[0-9a-f]+: (R_386_32|dir32)[ ]+sym +[ ]*[0-9a-f]+:[ ]+c7 00 f4 00 00 00 movl \$0xf4,\(%eax\)[ ]+[0-9a-f]+: (R_386_32|dir32)[ ]+sym +[ ]*[0-9a-f]+:[ ]+c7 02 f4 00 00 00 movl \$0xf4,\(%edx\)[ ]+[0-9a-f]+: (R_386_32|dir32)[ ]+sym +[ ]*[0-9a-f]+:[ ]+81 c1 f4 00 00 00 add \$0xf4,%ecx +[ ]*[0-9a-f]+:[ ]+81 c2 f4 00 00 00 add \$0xf4,%edx +[ ]*[0-9a-f]+:[ ]+81 c1 90 00 00 00 add \$0x90,%ecx +[ ]*[0-9a-f]+:[ ]+81 c2 90 00 00 00 add \$0x90,%edx +[ ]*[0-9a-f]+:[ ]+81 c1 00 ff ff ff add \$0xffffff00,%ecx[ ]+[0-9a-f]+: (R_386_32|dir32)[ ]+sym +[ ]*[0-9a-f]+:[ ]+81 c2 00 ff ff ff add \$0xffffff00,%edx[ ]+[0-9a-f]+: (R_386_32|dir32)[ ]+sym +[ ]*[0-9a-f]+:[ ]+81 c1 f4 00 00 00 add \$0xf4,%ecx[ ]+[0-9a-f]+: (R_386_32|dir32)[ ]+sym +[ ]*[0-9a-f]+:[ ]+81 c2 f4 00 00 00 add \$0xf4,%edx[ ]+[0-9a-f]+: (R_386_32|dir32)[ ]+sym +[ ]*[0-9a-f]+:[ ]+81 00 f4 00 00 00 addl \$0xf4,\(%eax\) +[ ]*[0-9a-f]+:[ ]+81 02 f4 00 00 00 addl \$0xf4,\(%edx\) +[ ]*[0-9a-f]+:[ ]+81 00 90 00 00 00 addl \$0x90,\(%eax\) +[ ]*[0-9a-f]+:[ ]+81 02 90 00 00 00 addl \$0x90,\(%edx\) +[ ]*[0-9a-f]+:[ ]+81 00 00 ff ff ff addl \$0xffffff00,\(%eax\)[ ]+[0-9a-f]+: (R_386_32|dir32)[ ]+sym +[ ]*[0-9a-f]+:[ ]+81 02 00 ff ff ff addl \$0xffffff00,\(%edx\)[ ]+[0-9a-f]+: (R_386_32|dir32)[ ]+sym +[ ]*[0-9a-f]+:[ ]+81 00 f4 00 00 00 addl \$0xf4,\(%eax\)[ ]+[0-9a-f]+: (R_386_32|dir32)[ ]+sym +[ ]*[0-9a-f]+:[ ]+81 02 f4 00 00 00 addl \$0xf4,\(%edx\)[ ]+[0-9a-f]+: (R_386_32|dir32)[ ]+sym +[ ]*[0-9a-f]+:[ ]+c3 ret * +#pass diff --git a/gas/testsuite/gas/i386/wrap32.s b/gas/testsuite/gas/i386/wrap32.s new file mode 100644 index 00000000000..01984846441 --- /dev/null +++ b/gas/testsuite/gas/i386/wrap32.s @@ -0,0 +1,60 @@ + .text +wrap: + mov $500 - 0x100, %eax + mov $500 + 0xffffff00, %edx + mov $val - 0x100, %eax + mov $val + 0xffffff00, %edx + mov $sym - 0x100, %eax + mov $sym + 0xffffff00, %edx + mov $sym + 500 - 0x100, %eax + mov $sym + 500 + 0xffffff00, %edx + + movl $500 - 0x100, (%eax) + movl $500 + 0xffffff00, (%edx) + movl $val - 0x100, (%eax) + movl $val + 0xffffff00, (%edx) + movl $sym - 0x100, (%eax) + movl $sym + 0xffffff00, (%edx) + movl $sym + 500 - 0x100, (%eax) + movl $sym + 500 + 0xffffff00, (%edx) + + add $500 - 0x100, %ecx + add $500 + 0xffffff00, %edx + add $val - 0x100, %ecx + add $val + 0xffffff00, %edx + add $sym - 0x100, %ecx + add $sym + 0xffffff00, %edx + add $sym + 500 - 0x100, %ecx + add $sym + 500 + 0xffffff00, %edx + + addl $500 - 0x100, (%eax) + addl $500 + 0xffffff00, (%edx) + addl $val - 0x100, (%eax) + addl $val + 0xffffff00, (%edx) + addl $sym - 0x100, (%eax) + addl $sym + 0xffffff00, (%edx) + addl $sym + 500 - 0x100, (%eax) + addl $sym + 500 + 0xffffff00, (%edx) + + ret + + .data + .long 500 - 0x100 + .long 500 + 0xffffff00 + .long val - 0x100 + .long val + 0xffffff00 + .long sym - 0x100 + .long sym + 0xffffff00 + .long sym + 500 - 0x100 + .long sym + 500 + 0xffffff00 + + .slong 500 - 0x8fffff00 + .slong 500 + 0x7fffff00 + .slong val - 0x8fffff00 + .slong val + 0x7fffff00 + .slong sym - 0x8fffff00 + .slong sym + 0x7fffff00 + .slong sym + 500 - 0x8fffff00 + .slong sym + 500 + 0x7fffff00 + + .equ val, 400 -- 2.30.2