[llvm-commits] [llvm] r134641 - in /llvm/trunk: lib/Target/X86/MCTargetDesc/X86MCTargetDesc.cpp lib/Target/X86/MCTargetDesc/X86MCTargetDesc.h lib/Target/X86/X86.td lib/Target/X86/X86Subtarget.cpp lib/Target/X86/X86Subtarget.h lib/Target/X86/X86Ta

[Evan Cheng]

On Jul 8, 2011, at 2:55 PM, Eli Friedman wrote:

> On Fri, Jul 8, 2011 at 2:54 PM, Evan Cheng <evan.cheng at apple.com> wrote:
>> 
>> On Jul 8, 2011, at 2:35 PM, Eli Friedman wrote:
>> 
>>> On Fri, Jul 8, 2011 at 2:15 PM, Evan Cheng <evan.cheng at apple.com> wrote:
>>>> r134741 should handle the non-x86 hosts. For the other cases, we should either fix tests or add specific CPUs to X86.td.
>>> 
>>> r134741 does't help at all.  Consider the case where we're compiling
>>> for a triple like x86_64-apple-macosx10.7.0, no CPU is specified, and
>>> we're on ARM.  We end up in 64-bit mode, but with cmov and SSE
>>> disabled.  Stuff explodes.
>> 
>> That's why this hack is in X86Subtarget.cpp:
>> 
>>  // If requesting codegen for X86-64, make sure that 64-bit features
>>  // are enabled.
>>  // FIXME: Remove this feature since it's not actually being used.
>>  if (In64BitMode) {
>>    HasX86_64 = true;
>> 
>>    // All 64-bit cpus have cmov support.
>>    HasCMov = true;
>>  }
> 
> In64BitMode is unconditionally false.

No ParseSubtargetFeatures can set it:
  if ((Bits & X86::Mode64Bit) != 0) In64BitMode = true;

Evan

> 
> -Eli