commit 7eb902bc9272afb419ab6fc5699eb7ed8beb104b Author: H.J. Lu Date: Thu Feb 9 22:51:57 2012 +0000 Don't use multi byte nop instructions for i386 bfd/ 2012-02-09 H.J. Lu PR ld/13675 * cpu-i386.c (bfd_arch_i386_fill): Updated to support multi byte nop instructions. (bfd_arch_i386_short_nop_fill): New. (bfd_arch_i386_long_nop_fill): Likewise. Use bfd_arch_i386_short_nop_fill in 32bit bfd_arch_info initializers. Use bfd_arch_i386_long_nop_fill on 64bit bfd_arch_info initializers. * cpu-k1om.c (bfd_arch_i386_fill): Renamed to ... (bfd_arch_i386_short_nop_fill): This. Update bfd_arch_info initializers. * cpu-l1om.c: Likewise. ld/testsuite/ 2012-02-09 H.J. Lu PR ld/13675 * ld-i386/tlsnopic.dd: Update no-op padding. * ld-i386/tlspic.dd: Likewise. diff --git a/bfd/cpu-i386.c b/bfd/cpu-i386.c index f8991cf..4cb59ed 100644 --- a/bfd/cpu-i386.c +++ b/bfd/cpu-i386.c @@ -25,7 +25,8 @@ #include "libbfd.h" #include "libiberty.h" -extern void * bfd_arch_i386_fill (bfd_size_type, bfd_boolean, bfd_boolean); +extern void * bfd_arch_i386_short_nop_fill (bfd_size_type, bfd_boolean, + bfd_boolean); static const bfd_arch_info_type * bfd_i386_compatible (const bfd_arch_info_type *a, @@ -41,16 +42,16 @@ bfd_i386_compatible (const bfd_arch_info_type *a, return compat; } -/* Fill the buffer with zero or nop instruction if CODE is TRUE. */ +/* Fill the buffer with zero or nop instruction if CODE is TRUE. Use + multi byte nop instructions if LONG_NOP is TRUE. */ -void * -bfd_arch_i386_fill (bfd_size_type count, - bfd_boolean is_bigendian ATTRIBUTE_UNUSED, - bfd_boolean code) +static void * +bfd_arch_i386_fill (bfd_size_type count, bfd_boolean code, + bfd_boolean long_nop) { /* nop */ static const char nop_1[] = { 0x90 }; - /* nopw */ + /* xchg %ax,%ax */ static const char nop_2[] = { 0x66, 0x90 }; /* nopl (%[re]ax) */ static const char nop_3[] = { 0x0f, 0x1f, 0x00 }; @@ -74,6 +75,7 @@ bfd_arch_i386_fill (bfd_size_type count, static const char *const nops[] = { nop_1, nop_2, nop_3, nop_4, nop_5, nop_6, nop_7, nop_8, nop_9, nop_10 }; + bfd_size_type nop_size = long_nop ? ARRAY_SIZE (nops) : 2; void *fill = bfd_malloc (count); if (fill == NULL) @@ -82,11 +84,11 @@ bfd_arch_i386_fill (bfd_size_type count, if (code) { bfd_byte *p = fill; - while (count >= ARRAY_SIZE (nops)) + while (count >= nop_size) { - memcpy (p, nops[ARRAY_SIZE (nops) - 1], ARRAY_SIZE (nops)); - p += ARRAY_SIZE (nops); - count -= ARRAY_SIZE (nops); + memcpy (p, nops[nop_size - 1], nop_size); + p += nop_size; + count -= nop_size; } if (count != 0) memcpy (p, nops[count - 1], count); @@ -97,6 +99,26 @@ bfd_arch_i386_fill (bfd_size_type count, return fill; } +/* Fill the buffer with zero or short nop instruction if CODE is TRUE. */ + +void * +bfd_arch_i386_short_nop_fill (bfd_size_type count, + bfd_boolean is_bigendian ATTRIBUTE_UNUSED, + bfd_boolean code) +{ + return bfd_arch_i386_fill (count, code, FALSE); +} + +/* Fill the buffer with zero or long nop instruction if CODE is TRUE. */ + +static void * +bfd_arch_i386_long_nop_fill (bfd_size_type count, + bfd_boolean is_bigendian ATTRIBUTE_UNUSED, + bfd_boolean code) +{ + return bfd_arch_i386_fill (count, code, TRUE); +} + static const bfd_arch_info_type bfd_x64_32_arch_intel_syntax = { 64, /* 64 bits in a word */ @@ -110,7 +132,7 @@ static const bfd_arch_info_type bfd_x64_32_arch_intel_syntax = FALSE, bfd_i386_compatible, bfd_default_scan, - bfd_arch_i386_fill, + bfd_arch_i386_long_nop_fill, 0 }; @@ -127,7 +149,7 @@ static const bfd_arch_info_type bfd_x86_64_arch_intel_syntax = FALSE, bfd_i386_compatible, bfd_default_scan, - bfd_arch_i386_fill, + bfd_arch_i386_long_nop_fill, &bfd_x64_32_arch_intel_syntax, }; @@ -144,7 +166,7 @@ static const bfd_arch_info_type bfd_i386_arch_intel_syntax = TRUE, bfd_i386_compatible, bfd_default_scan, - bfd_arch_i386_fill, + bfd_arch_i386_short_nop_fill, &bfd_x86_64_arch_intel_syntax }; @@ -161,7 +183,7 @@ static const bfd_arch_info_type i8086_arch = FALSE, bfd_i386_compatible, bfd_default_scan, - bfd_arch_i386_fill, + bfd_arch_i386_short_nop_fill, &bfd_i386_arch_intel_syntax }; @@ -178,7 +200,7 @@ static const bfd_arch_info_type bfd_x64_32_arch = FALSE, bfd_i386_compatible, bfd_default_scan, - bfd_arch_i386_fill, + bfd_arch_i386_long_nop_fill, &i8086_arch }; @@ -195,7 +217,7 @@ static const bfd_arch_info_type bfd_x86_64_arch = FALSE, bfd_i386_compatible, bfd_default_scan, - bfd_arch_i386_fill, + bfd_arch_i386_long_nop_fill, &bfd_x64_32_arch }; @@ -212,6 +234,6 @@ const bfd_arch_info_type bfd_i386_arch = TRUE, bfd_i386_compatible, bfd_default_scan, - bfd_arch_i386_fill, + bfd_arch_i386_short_nop_fill, &bfd_x86_64_arch }; diff --git a/bfd/cpu-k1om.c b/bfd/cpu-k1om.c index f9958e4..54b6e58 100644 --- a/bfd/cpu-k1om.c +++ b/bfd/cpu-k1om.c @@ -23,7 +23,8 @@ #include "bfd.h" #include "libbfd.h" -extern void * bfd_arch_i386_fill (bfd_size_type, bfd_boolean, bfd_boolean); +extern void * bfd_arch_i386_short_nop_fill (bfd_size_type, bfd_boolean, + bfd_boolean); static const bfd_arch_info_type bfd_k1om_arch_intel_syntax = { @@ -38,7 +39,7 @@ static const bfd_arch_info_type bfd_k1om_arch_intel_syntax = TRUE, bfd_default_compatible, bfd_default_scan, - bfd_arch_i386_fill, + bfd_arch_i386_short_nop_fill, 0 }; @@ -55,6 +56,6 @@ const bfd_arch_info_type bfd_k1om_arch = TRUE, bfd_default_compatible, bfd_default_scan, - bfd_arch_i386_fill, + bfd_arch_i386_short_nop_fill, &bfd_k1om_arch_intel_syntax }; diff --git a/bfd/cpu-l1om.c b/bfd/cpu-l1om.c index 0fabd49..46ac3a0 100644 --- a/bfd/cpu-l1om.c +++ b/bfd/cpu-l1om.c @@ -23,7 +23,8 @@ #include "bfd.h" #include "libbfd.h" -extern void * bfd_arch_i386_fill (bfd_size_type, bfd_boolean, bfd_boolean); +extern void * bfd_arch_i386_short_nop_fill (bfd_size_type, bfd_boolean, + bfd_boolean); static const bfd_arch_info_type bfd_l1om_arch_intel_syntax = { @@ -38,7 +39,7 @@ static const bfd_arch_info_type bfd_l1om_arch_intel_syntax = TRUE, bfd_default_compatible, bfd_default_scan, - bfd_arch_i386_fill, + bfd_arch_i386_short_nop_fill, 0 }; @@ -55,6 +56,6 @@ const bfd_arch_info_type bfd_l1om_arch = TRUE, bfd_default_compatible, bfd_default_scan, - bfd_arch_i386_fill, + bfd_arch_i386_short_nop_fill, &bfd_l1om_arch_intel_syntax }; diff --git a/ld/testsuite/ChangeLog b/ld/testsuite/ChangeLog index 037bfa0..b53cb8b 100644 --- a/ld/testsuite/ChangeLog +++ b/ld/testsuite/ChangeLog @@ -1,3 +1,9 @@ +2012-02-09 H.J. Lu + + PR ld/13675 + * ld-i386/tlsnopic.dd: Update no-op padding. + * ld-i386/tlspic.dd: Likewise. + 2012-01-31 H.J. Lu PR ld/13616 diff --git a/ld/testsuite/ld-i386/tlsnopic.dd b/ld/testsuite/ld-i386/tlsnopic.dd index d6a16d0..027d288 100644 --- a/ld/testsuite/ld-i386/tlsnopic.dd +++ b/ld/testsuite/ld-i386/tlsnopic.dd @@ -156,4 +156,5 @@ Disassembly of section .text: 10ec: 8b 5d fc[ ]+mov -0x4\(%ebp\),%ebx 10ef: c9[ ]+leave * 10f0: c3[ ]+ret * - 10f1: 0f 1f 00[ ]+nopl \(%eax\) + 10f1: 66 90[ ]+xchg %ax,%ax + 10f3: 90[ ]+nop diff --git a/ld/testsuite/ld-i386/tlspic.dd b/ld/testsuite/ld-i386/tlspic.dd index d85b385..ace06e6 100644 --- a/ld/testsuite/ld-i386/tlspic.dd +++ b/ld/testsuite/ld-i386/tlspic.dd @@ -406,4 +406,5 @@ Disassembly of section .text: [0-9a-f]+: 8b 5d fc[ ]+mov -0x4\(%ebp\),%ebx [0-9a-f]+: c9[ ]+leave * [0-9a-f]+: c3[ ]+ret * - [0-9a-f]+: 0f 1f 00[ ]+nopl \(%eax\) + [0-9a-f]+: 66 90[ ]+xchg %ax,%ax + [0-9a-f]+: 90[ ]+nop