From 02e2aef89bb58e8e0cc4390db41c5f775e1b7c3e Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Fri, 4 Dec 2015 08:43:45 -0800 Subject: [PATCH] Optimize R_386_GOT32/R_386_GOT32X only if addend is 0 Linker can't optimize R_386_GOT32 and R_386_GOT32X relocations if addend isn't 0. It isn't valid to convert movl foo@GOT+1(%ecx), %eax to leal foo@GOTOFF+1(%ecx), %eax nor to convert movq foo@GOTPCREL+1(%rip), %rax to leaq foo(%rip), %rax for x86-64. We should check if addend is 0 before optimizing R_386_GOT32 and R_386_GOT32X relocations. Testcases are added for i386 and x86-64. bfd/ * elf32-i386.c (elf_i386_convert_load): Skip if addend isn't 0. (elf_i386_relocate_section): Skip R_386_GOT32X optimization if addend isn't 0. ld/testsuite/ * ld-i386/i386.exp: Run mov2a, mov2b and mov3. * ld-i386/mov2.s: New file. * ld-i386/mov2a.d: Likewise. * ld-i386/mov2b.d: Likewise. * ld-i386/mov3.d: Likewise. * ld-i386/mov3.s: Likewise. * ld-x86-64/mov2.s: Likewise. * ld-x86-64/mov2a.d: Likewise. * ld-x86-64/mov2b.d: Likewise. * ld-x86-64/mov2c.d: Likewise. * ld-x86-64/mov2d.d: Likewise. * ld-x86-64/x86-64.exp: Run mov2a, mov2b, mov2c and mov2d. --- bfd/ChangeLog | 6 ++++++ bfd/elf32-i386.c | 24 +++++++++++------------- ld/testsuite/ChangeLog | 13 +++++++++++++ ld/testsuite/ld-i386/i386.exp | 3 +++ ld/testsuite/ld-i386/mov2.s | 15 +++++++++++++++ ld/testsuite/ld-i386/mov2a.d | 15 +++++++++++++++ ld/testsuite/ld-i386/mov2b.d | 15 +++++++++++++++ ld/testsuite/ld-i386/mov3.d | 14 ++++++++++++++ ld/testsuite/ld-i386/mov3.s | 15 +++++++++++++++ ld/testsuite/ld-x86-64/mov2.s | 15 +++++++++++++++ ld/testsuite/ld-x86-64/mov2a.d | 15 +++++++++++++++ ld/testsuite/ld-x86-64/mov2b.d | 15 +++++++++++++++ ld/testsuite/ld-x86-64/mov2c.d | 15 +++++++++++++++ ld/testsuite/ld-x86-64/mov2d.d | 15 +++++++++++++++ ld/testsuite/ld-x86-64/x86-64.exp | 4 ++++ 15 files changed, 186 insertions(+), 13 deletions(-) create mode 100644 ld/testsuite/ld-i386/mov2.s create mode 100644 ld/testsuite/ld-i386/mov2a.d create mode 100644 ld/testsuite/ld-i386/mov2b.d create mode 100644 ld/testsuite/ld-i386/mov3.d create mode 100644 ld/testsuite/ld-i386/mov3.s create mode 100644 ld/testsuite/ld-x86-64/mov2.s create mode 100644 ld/testsuite/ld-x86-64/mov2a.d create mode 100644 ld/testsuite/ld-x86-64/mov2b.d create mode 100644 ld/testsuite/ld-x86-64/mov2c.d create mode 100644 ld/testsuite/ld-x86-64/mov2d.d diff --git a/bfd/ChangeLog b/bfd/ChangeLog index ab717eae16..e810dbe1c8 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,3 +1,9 @@ +2015-12-04 H.J. Lu + + * elf32-i386.c (elf_i386_convert_load): Skip if addend isn't 0. + (elf_i386_relocate_section): Skip R_386_GOT32X optimization if + addend isn't 0. + 2015-12-04 Tristan Gingold * elf.c (rewrite_elf_program_header): Remove useless loop. diff --git a/bfd/elf32-i386.c b/bfd/elf32-i386.c index ae3187dc3f..300839b279 100644 --- a/bfd/elf32-i386.c +++ b/bfd/elf32-i386.c @@ -2820,6 +2820,11 @@ elf_i386_convert_load (bfd *abfd, asection *sec, if (roff < 2) continue; + /* Addend for R_386_GOT32 and R_386_GOT32X relocations must be 0. */ + addend = bfd_get_32 (abfd, contents + roff); + if (addend != 0) + continue; + modrm = bfd_get_8 (abfd, contents + roff - 1); baseless = (modrm & 0xc7) == 0x5; @@ -2913,11 +2918,6 @@ elf_i386_convert_load (bfd *abfd, asection *sec, { /* The function is locally defined. */ convert_branch: - addend = bfd_get_32 (abfd, contents + roff); - /* Addend for R_386_GOT32X relocation must be 0. */ - if (addend != 0) - continue; - /* Convert R_386_GOT32X to R_386_PC32. */ if (modrm == 0x15 || (modrm & 0xf8) == 0x90) { @@ -3007,11 +3007,6 @@ convert_load: } else { - /* Addend for R_386_GOT32X relocation must be 0. */ - addend = bfd_get_32 (abfd, contents + roff); - if (addend != 0) - continue; - if (opcode == 0x85) { /* Convert "test %reg1, foo@GOT(%reg2)" to @@ -3998,8 +3993,11 @@ elf_i386_relocate_section (bfd *output_bfd, branch to direct branch. It is OK to convert adc, add, and, cmp, or, sbb, sub, test, xor only when PIC is false. */ - unsigned int opcode; - opcode = bfd_get_8 (abfd, contents + rel->r_offset - 2); + unsigned int opcode, addend; + addend = bfd_get_32 (input_bfd, contents + rel->r_offset); + if (addend != 0) + goto r_386_got32; + opcode = bfd_get_8 (input_bfd, contents + rel->r_offset - 2); if (opcode != 0x8b && opcode != 0xff) goto r_386_got32; } @@ -4031,7 +4029,7 @@ elf_i386_relocate_section (bfd *output_bfd, /* If not PIC, add the .got.plt section address for baseless addressing. */ unsigned int modrm; - modrm = bfd_get_8 (abfd, contents + rel->r_offset - 1); + modrm = bfd_get_8 (input_bfd, contents + rel->r_offset - 1); if ((modrm & 0xc7) == 0x5) relocation += offplt; } diff --git a/ld/testsuite/ChangeLog b/ld/testsuite/ChangeLog index d7ef3c41d4..f0ca10591a 100644 --- a/ld/testsuite/ChangeLog +++ b/ld/testsuite/ChangeLog @@ -1,3 +1,16 @@ +2015-12-04 H.J. Lu + + * ld-i386/i386.exp: Run mov2a and mov2b. + * ld-i386/mov2.s: New file. + * ld-i386/mov2a.d: Likewise. + * ld-i386/mov2b.d: Likewise. + * ld-x86-64/mov2.s: Likewise. + * ld-x86-64/mov2a.d: Likewise. + * ld-x86-64/mov2b.d: Likewise. + * ld-x86-64/mov2c.d: Likewise. + * ld-x86-64/mov2d.d: Likewise. + * ld-x86-64/x86-64.exp: Run mov2a, mov2b, mov2c and mov2d. + 2015-12-01 H.J. Lu PR ld/19319 diff --git a/ld/testsuite/ld-i386/i386.exp b/ld/testsuite/ld-i386/i386.exp index a6601ed822..fb1d3eafb6 100644 --- a/ld/testsuite/ld-i386/i386.exp +++ b/ld/testsuite/ld-i386/i386.exp @@ -293,6 +293,9 @@ run_dump_test "lea1e" run_dump_test "lea1f" run_dump_test "mov1a" run_dump_test "mov1b" +run_dump_test "mov2a" +run_dump_test "mov2b" +run_dump_test "mov3" run_dump_test "branch1" run_dump_test "call1" run_dump_test "call2" diff --git a/ld/testsuite/ld-i386/mov2.s b/ld/testsuite/ld-i386/mov2.s new file mode 100644 index 0000000000..3fa06ceec8 --- /dev/null +++ b/ld/testsuite/ld-i386/mov2.s @@ -0,0 +1,15 @@ + .section my_section,"aw",@progbits + .long 0x12345678 + .text + .globl foo + .type foo, @function +foo: + ret + .size foo, .-foo + .globl _start + .type _start, @function +_start: + movl foo@GOT+1(%ecx), %eax + movl __start_my_section@GOT+1(%ecx), %eax + movl __stop_my_section@GOT+1(%ecx), %eax + .size _start, .-_start diff --git a/ld/testsuite/ld-i386/mov2a.d b/ld/testsuite/ld-i386/mov2a.d new file mode 100644 index 0000000000..d8756e5514 --- /dev/null +++ b/ld/testsuite/ld-i386/mov2a.d @@ -0,0 +1,15 @@ +#source: mov2.s +#as: --32 +#ld: -shared -melf_i386 +#objdump: -dw + +.*: +file format .* + + +Disassembly of section .text: + +#... +[ ]*[a-f0-9]+: 8b 81 ([0-9a-f]{2} ){4} * mov -0x[a-f0-9]+\(%ecx\),%eax +[ ]*[a-f0-9]+: 8b 81 ([0-9a-f]{2} ){4} * mov -0x[a-f0-9]+\(%ecx\),%eax +[ ]*[a-f0-9]+: 8b 81 ([0-9a-f]{2} ){4} * mov -0x[a-f0-9]+\(%ecx\),%eax +#pass diff --git a/ld/testsuite/ld-i386/mov2b.d b/ld/testsuite/ld-i386/mov2b.d new file mode 100644 index 0000000000..ea5dd9ba39 --- /dev/null +++ b/ld/testsuite/ld-i386/mov2b.d @@ -0,0 +1,15 @@ +#source: mov2.s +#as: --32 +#ld: -pie -melf_i386 +#objdump: -dw + +.*: +file format .* + + +Disassembly of section .text: + +#... +[ ]*[a-f0-9]+: 8b 81 ([0-9a-f]{2} ){4} * mov -0x[a-f0-9]+\(%ecx\),%eax +[ ]*[a-f0-9]+: 8b 81 ([0-9a-f]{2} ){4} * mov -0x[a-f0-9]+\(%ecx\),%eax +[ ]*[a-f0-9]+: 8b 81 ([0-9a-f]{2} ){4} * mov -0x[a-f0-9]+\(%ecx\),%eax +#pass diff --git a/ld/testsuite/ld-i386/mov3.d b/ld/testsuite/ld-i386/mov3.d new file mode 100644 index 0000000000..17da244ba1 --- /dev/null +++ b/ld/testsuite/ld-i386/mov3.d @@ -0,0 +1,14 @@ +#as: --32 +#ld: -melf_i386 +#objdump: -dw + +.*: +file format .* + + +Disassembly of section .text: + +#... +[ ]*[a-f0-9]+: 8b 05 ([0-9a-f]{2} ){4} * mov 0x[a-f0-9]+\,%eax +[ ]*[a-f0-9]+: 8b 05 ([0-9a-f]{2} ){4} * mov 0x[a-f0-9]+\,%eax +[ ]*[a-f0-9]+: 8b 05 ([0-9a-f]{2} ){4} * mov 0x[a-f0-9]+\,%eax +#pass diff --git a/ld/testsuite/ld-i386/mov3.s b/ld/testsuite/ld-i386/mov3.s new file mode 100644 index 0000000000..0dc54eb72f --- /dev/null +++ b/ld/testsuite/ld-i386/mov3.s @@ -0,0 +1,15 @@ + .section my_section,"aw",@progbits + .long 0x12345678 + .text + .globl foo + .type foo, @function +foo: + ret + .size foo, .-foo + .globl _start + .type _start, @function +_start: + movl foo@GOT+1, %eax + movl __start_my_section@GOT+1, %eax + movl __stop_my_section@GOT+1, %eax + .size _start, .-_start diff --git a/ld/testsuite/ld-x86-64/mov2.s b/ld/testsuite/ld-x86-64/mov2.s new file mode 100644 index 0000000000..95e474f030 --- /dev/null +++ b/ld/testsuite/ld-x86-64/mov2.s @@ -0,0 +1,15 @@ + .section my_section,"aw",@progbits + .long 0x12345678 + .text + .globl foo + .type foo, @function +foo: + ret + .size foo, .-foo + .globl _start + .type _start, @function +_start: + movq foo@GOTPCREL+1(%rip), %rax + movq __start_my_section@GOTPCREL+1(%rip), %rax + movq __stop_my_section@GOTPCREL+1(%rip), %rax + .size _start, .-_start diff --git a/ld/testsuite/ld-x86-64/mov2a.d b/ld/testsuite/ld-x86-64/mov2a.d new file mode 100644 index 0000000000..aaf57070b1 --- /dev/null +++ b/ld/testsuite/ld-x86-64/mov2a.d @@ -0,0 +1,15 @@ +#source: mov2.s +#as: --64 +#ld: -shared -melf_x86_64 +#objdump: -dw + +.*: +file format .* + + +Disassembly of section .text: + +#... +[ ]*[a-f0-9]+: 48 8b 05 ([0-9a-f]{2} ){4} * mov 0x[a-f0-9]+\(%rip\),%rax # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+> +[ ]*[a-f0-9]+: 48 8b 05 ([0-9a-f]{2} ){4} * mov 0x[a-f0-9]+\(%rip\),%rax # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+> +[ ]*[a-f0-9]+: 48 8b 05 ([0-9a-f]{2} ){4} * mov 0x[a-f0-9]+\(%rip\),%rax # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+> +#pass diff --git a/ld/testsuite/ld-x86-64/mov2b.d b/ld/testsuite/ld-x86-64/mov2b.d new file mode 100644 index 0000000000..ee1b308b6b --- /dev/null +++ b/ld/testsuite/ld-x86-64/mov2b.d @@ -0,0 +1,15 @@ +#source: mov2.s +#as: --64 +#ld: -pie -melf_x86_64 +#objdump: -dw + +.*: +file format .* + + +Disassembly of section .text: + +#... +[ ]*[a-f0-9]+: 48 8b 05 ([0-9a-f]{2} ){4} * mov 0x[a-f0-9]+\(%rip\),%rax # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+> +[ ]*[a-f0-9]+: 48 8b 05 ([0-9a-f]{2} ){4} * mov 0x[a-f0-9]+\(%rip\),%rax # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+> +[ ]*[a-f0-9]+: 48 8b 05 ([0-9a-f]{2} ){4} * mov 0x[a-f0-9]+\(%rip\),%rax # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+> +#pass diff --git a/ld/testsuite/ld-x86-64/mov2c.d b/ld/testsuite/ld-x86-64/mov2c.d new file mode 100644 index 0000000000..8991121062 --- /dev/null +++ b/ld/testsuite/ld-x86-64/mov2c.d @@ -0,0 +1,15 @@ +#source: mov2.s +#as: --x32 +#ld: -shared -melf32_x86_64 +#objdump: -dw + +.*: +file format .* + + +Disassembly of section .text: + +#... +[ ]*[a-f0-9]+: 48 8b 05 ([0-9a-f]{2} ){4} * mov 0x[a-f0-9]+\(%rip\),%rax # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+> +[ ]*[a-f0-9]+: 48 8b 05 ([0-9a-f]{2} ){4} * mov 0x[a-f0-9]+\(%rip\),%rax # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+> +[ ]*[a-f0-9]+: 48 8b 05 ([0-9a-f]{2} ){4} * mov 0x[a-f0-9]+\(%rip\),%rax # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+> +#pass diff --git a/ld/testsuite/ld-x86-64/mov2d.d b/ld/testsuite/ld-x86-64/mov2d.d new file mode 100644 index 0000000000..744028e640 --- /dev/null +++ b/ld/testsuite/ld-x86-64/mov2d.d @@ -0,0 +1,15 @@ +#source: mov2.s +#as: --x32 +#ld: -pie -melf32_x86_64 +#objdump: -dw + +.*: +file format .* + + +Disassembly of section .text: + +#... +[ ]*[a-f0-9]+: 48 8b 05 ([0-9a-f]{2} ){4} * mov 0x[a-f0-9]+\(%rip\),%rax # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+> +[ ]*[a-f0-9]+: 48 8b 05 ([0-9a-f]{2} ){4} * mov 0x[a-f0-9]+\(%rip\),%rax # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+> +[ ]*[a-f0-9]+: 48 8b 05 ([0-9a-f]{2} ){4} * mov 0x[a-f0-9]+\(%rip\),%rax # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+> +#pass diff --git a/ld/testsuite/ld-x86-64/x86-64.exp b/ld/testsuite/ld-x86-64/x86-64.exp index f0f47eb891..45b7f094ba 100644 --- a/ld/testsuite/ld-x86-64/x86-64.exp +++ b/ld/testsuite/ld-x86-64/x86-64.exp @@ -321,6 +321,10 @@ run_dump_test "mov1a" run_dump_test "mov1b" run_dump_test "mov1c" run_dump_test "mov1d" +run_dump_test "mov2a" +run_dump_test "mov2b" +run_dump_test "mov2c" +run_dump_test "mov2d" run_dump_test "load1a" run_dump_test "load1b" run_dump_test "load1c"