From fb0576e98388c6f4585b94684cea8d18c97a91aa Mon Sep 17 00:00:00 2001 From: Doug Evans Date: Thu, 28 Aug 2014 11:38:22 -0700 Subject: [PATCH] Rewrite {amd64,i386}-pseudo.c to better specify register liveness. clang was using eax to construct %0 here: asm ("mov %%eax, 0(%0)\n\t" "mov %%ebx, 4(%0)\n\t" "mov %%ecx, 8(%0)\n\t" "mov %%edx, 12(%0)\n\t" "mov %%esi, 16(%0)\n\t" "mov %%edi, 20(%0)\n\t" : /* no output operands */ : "r" (data) : "eax", "ebx", "ecx", "edx", "esi", "edi"); which caused amd64-word.exp (and others similarly) to fail. It's a perfectly legit thing for clang to do given the available data. The patch fixes this by marking the registers as live from the time of the preceding breakpoint. gdb/testsuite/ChangeLog: * gdb.arch/amd64-pseudo.c (main): Rewrite to better specify when eax,etc. are live with values set by gdb and thus the compiler can't use them. * gdb.arch/i386-pseudo.c (main): Ditto. --- gdb/testsuite/ChangeLog | 7 ++++ gdb/testsuite/gdb.arch/amd64-pseudo.c | 57 +++++++++++++++++---------- gdb/testsuite/gdb.arch/i386-pseudo.c | 18 +++++++-- 3 files changed, 59 insertions(+), 23 deletions(-) diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog index 4a65fef02e7..d996b7c2897 100644 --- a/gdb/testsuite/ChangeLog +++ b/gdb/testsuite/ChangeLog @@ -1,3 +1,10 @@ +2014-08-28 Doug Evans + + * gdb.arch/amd64-pseudo.c (main): Rewrite to better specify when + eax,etc. are live with values set by gdb and thus the compiler can't + use them. + * gdb.arch/i386-pseudo.c (main): Ditto. + 2014-08-27 Doug Evans * lib/gdb.exp (gdb_compile_shlib): Add support for clang. diff --git a/gdb/testsuite/gdb.arch/amd64-pseudo.c b/gdb/testsuite/gdb.arch/amd64-pseudo.c index 4dac1f1ce33..f6fd0e7412f 100644 --- a/gdb/testsuite/gdb.arch/amd64-pseudo.c +++ b/gdb/testsuite/gdb.arch/amd64-pseudo.c @@ -39,6 +39,21 @@ int data[] = { int main (int argc, char **argv) { + register int eax asm ("eax"); + register int ebx asm ("ebx"); + register int ecx asm ("ecx"); + register int edx asm ("edx"); + register int esi asm ("esi"); + register int edi asm ("edi"); + register long r8 asm ("r8"); + register long r9 asm ("r9"); + register long r10 asm ("r10"); + register long r11 asm ("r11"); + register long r12 asm ("r12"); + register long r13 asm ("r13"); + register long r14 asm ("r14"); + register long r15 asm ("r15"); + asm ("mov 0(%0), %%eax\n\t" "mov 4(%0), %%ebx\n\t" "mov 8(%0), %%ecx\n\t" @@ -61,15 +76,13 @@ main (int argc, char **argv) : /* no output operands */ : "r" (data) : "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15"); - asm ("nop"); /* second breakpoint here */ - /* amd64-dword.exp writes eax-edi here. - Tell gcc they're clobbered so it doesn't try to keep "data" in - one of them. */ - asm ("" - : /* no outputs */ - : /* no inputs */ - : "eax", "ebx", "ecx", "edx", "esi", "edi"); + asm ("nop" /* second breakpoint here */ + /* amd64-{byte,word,dword}.exp write eax-edi here. + Tell gcc/clang they're live. */ + : "=r" (eax), "=r" (ebx), "=r" (ecx), + "=r" (edx), "=r" (esi), "=r" (edi) + : /* no inputs */); asm ("mov %%eax, 0(%0)\n\t" "mov %%ebx, 4(%0)\n\t" @@ -78,17 +91,18 @@ main (int argc, char **argv) "mov %%esi, 16(%0)\n\t" "mov %%edi, 20(%0)\n\t" : /* no output operands */ - : "r" (data) - : "eax", "ebx", "ecx", "edx", "esi", "edi"); - asm ("nop"); /* third breakpoint here */ + : "r" (data), + /* Mark these as inputs so that gcc/clang won't try to use them as + a temp to build %0. */ + "r" (eax), "r" (ebx), "r" (ecx), + "r" (edx), "r" (esi), "r" (edi)); - /* amd64-dword.exp writes r8-r15 here. - Tell gcc they're clobbered so it doesn't try to keep "data" in - one of them. */ - asm ("" - : /* no outputs */ - : /* no inputs */ - : "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15"); + asm ("nop" /* third breakpoint here */ + /* amd64-{byte,word,dword}.exp write r8-r15 here. + Tell gcc/clang they're live. */ + : "=r" (r8), "=r" (r9), "=r" (r10), "=r" (r11), + "=r" (r12), "=r" (r13), "=r" (r14), "=r" (r15) + : /* no inputs */); asm ("mov %%r8d, 24(%0)\n\t" "mov %%r9d, 28(%0)\n\t" @@ -99,8 +113,11 @@ main (int argc, char **argv) "mov %%r14d, 48(%0)\n\t" "mov %%r15d, 52(%0)\n\t" : /* no output operands */ - : "r" (data) - : "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15"); + : "r" (data), + /* Mark these as inputs so that gcc/clang won't try to use them as + a temp to build %0. */ + "r" (r8), "r" (r9), "r" (r10), "r" (r11), + "r" (r12), "r" (r13), "r" (r14), "r" (r15)); puts ("Bye!"); /* forth breakpoint here */ return 0; diff --git a/gdb/testsuite/gdb.arch/i386-pseudo.c b/gdb/testsuite/gdb.arch/i386-pseudo.c index 11cbcd55b75..34f6b9b0175 100644 --- a/gdb/testsuite/gdb.arch/i386-pseudo.c +++ b/gdb/testsuite/gdb.arch/i386-pseudo.c @@ -29,6 +29,11 @@ int data[] = { int main (int argc, char **argv) { + register int eax asm ("eax"); + register int ebx asm ("ebx"); + register int ecx asm ("ecx"); + register int edx asm ("edx"); + asm ("mov 0(%0), %%eax\n\t" "mov 4(%0), %%ebx\n\t" "mov 8(%0), %%ecx\n\t" @@ -36,15 +41,22 @@ main (int argc, char **argv) : /* no output operands */ : "r" (data) : "eax", "ebx", "ecx", "edx"); - asm ("nop"); /* first breakpoint here */ + + asm ("nop" /* first breakpoint here */ + /* i386-{byte,word}.exp write eax-edx here. + Tell gcc/clang they're live. */ + : "=r" (eax), "=r" (ebx), "=r" (ecx), "=r" (edx) + : /* no inputs */); asm ("mov %%eax, 0(%0)\n\t" "mov %%ebx, 4(%0)\n\t" "mov %%ecx, 8(%0)\n\t" "mov %%edx, 12(%0)\n\t" : /* no output operands */ - : "r" (data) - : "eax", "ebx", "ecx", "edx"); + : "r" (data), + /* Mark these as inputs so that gcc/clang won't try to use them as + a temp to build %0. */ + "r" (eax), "r" (ebx), "r" (ecx), "r" (edx)); puts ("Bye!"); /* second breakpoint here */ return 0; -- 2.30.2