svn commit: r271597 - head/contrib/llvm/lib/Target/X86

[Dimitry Andric]

Author: dim
Date: Sun Sep 14 18:50:38 2014
New Revision: 271597
URL: http://svnweb.freebsd.org/changeset/base/271597

Log:
  Pull in r217410 from upstream llvm trunk (by Bob Wilson):
  
    Set trunc store action to Expand for all X86 targets.
  
    When compiling without SSE2, isTruncStoreLegal(F64, F32) would return
    Legal, whereas with SSE2 it would return Expand. And since the Target
    doesn't seem to actually handle a truncstore for double -> float, it
    would just output a store of a full double in the space for a float
    hence overwriting other bits on the stack.
  
    Patch by Luqman Aden!
  
  This should fix clang -O0 on i386 assigning garbage to floats, in
  certain scenarios.
  
  PR:		187437
  Submitted by:	cebd at gmail.com
  Obtained from:	http://llvm.org/viewvc/llvm-project?rev=217410&view=rev
  MFC after:	3 days

Modified:
  head/contrib/llvm/lib/Target/X86/X86ISelLowering.cpp

Modified: head/contrib/llvm/lib/Target/X86/X86ISelLowering.cpp
==============================================================================
--- head/contrib/llvm/lib/Target/X86/X86ISelLowering.cpp	Sun Sep 14 18:07:55 2014	(r271596)
+++ head/contrib/llvm/lib/Target/X86/X86ISelLowering.cpp	Sun Sep 14 18:50:38 2014	(r271597)
@@ -300,6 +300,8 @@ void X86TargetLowering::resetOperationAc
   setTruncStoreAction(MVT::i32, MVT::i8 , Expand);
   setTruncStoreAction(MVT::i16, MVT::i8,  Expand);
 
+  setTruncStoreAction(MVT::f64, MVT::f32, Expand);
+
   // SETOEQ and SETUNE require checking two conditions.
   setCondCodeAction(ISD::SETOEQ, MVT::f32, Expand);
   setCondCodeAction(ISD::SETOEQ, MVT::f64, Expand);
@@ -1011,8 +1013,6 @@ void X86TargetLowering::resetOperationAc
       AddPromotedToType (ISD::SELECT, VT, MVT::v2i64);
     }
 
-    setTruncStoreAction(MVT::f64, MVT::f32, Expand);
-
     // Custom lower v2i64 and v2f64 selects.
     setOperationAction(ISD::LOAD,               MVT::v2f64, Legal);
     setOperationAction(ISD::LOAD,               MVT::v2i64, Legal);