diff options
| author | Paul Davis <paul@linuxaudiosystems.com> | 2009-12-31 17:53:10 +0000 |
|---|---|---|
| committer | Paul Davis <paul@linuxaudiosystems.com> | 2009-12-31 17:53:10 +0000 |
| commit | 05f68565cc5513223937eae620d9c7d676eff854 (patch) | |
| tree | 16646751cd656a669324a55a726fd6b41b826ca6 | |
| parent | 7269bab49c433f00665a34350de71f39a32bb2fb (diff) | |
asm fixes for FPU::FPU() back ported from 3.0
git-svn-id: svn://localhost/ardour2/branches/2.0-ongoing@6421 d708f5d6-7413-0410-9779-e7cbd77b26cf
| -rw-r--r-- | libs/pbd/fpu.cc | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/libs/pbd/fpu.cc b/libs/pbd/fpu.cc index ffb88714f6..a55166b139 100644 --- a/libs/pbd/fpu.cc +++ b/libs/pbd/fpu.cc @@ -21,6 +21,12 @@ FPU::FPU () #else + /* asm notes: although we explicitly save&restore ebx/rbx (stack pointer), we must tell + gcc that ebx,rbx is clobbered so that it doesn't try to use it as an intermediate + register when storing edx/rdx. gcc 4.3 didn't make this "mistake", but gcc 4.4 + does, at least on x86_64. + */ + #ifndef USE_X86_64_ASM asm volatile ( "mov $1, %%eax\n" @@ -30,7 +36,7 @@ FPU::FPU () "popl %%ebx\n" : "=r" (cpuflags) : - : "%eax", "%ecx", "%edx", "memory" + : "%eax", "%ebx", "%ecx", "%edx" ); #else @@ -43,7 +49,7 @@ FPU::FPU () "popq %%rbx\n" : "=r" (cpuflags) : - : "%rax", "%rcx", "%rdx", "memory" + : "%rax", "%rbx", "%rcx", "%rdx" ); #endif /* USE_X86_64_ASM */ @@ -69,6 +75,8 @@ FPU::FPU () error << _("cannot allocate 16 byte aligned buffer for h/w feature detection") << endmsg; } else { + memset (fxbuf, 0, 512); + asm volatile ( "fxsave (%0)" : |