[llvm-commits] [llvm] r51624 - /llvm/trunk/lib/Target/X86/X86ISelLowering.cpp

[Nate Begeman]

Author: sampo
Date: Tue May 27 19:24:25 2008
New Revision: 51624

URL: http://llvm.org/viewvc/llvm-project?rev=51624&view=rev
Log:
Don't attempt to create VZEXT_LOAD out of an extload.  This an issue where the
code generator would do something like this:

f64 = load f32 <anyext>, f32mem
v2f64 = insertelt undef, %0, 0
v2f64 = insertelt %1, 0.0, 1

into 

v2f64 = vzext_load f32mem

which on x86 is movsd, when you really wanted a cvtss2sd/movsd pair.


Modified:
    llvm/trunk/lib/Target/X86/X86ISelLowering.cpp

Modified: llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelLowering.cpp?rev=51624&r1=51623&r2=51624&view=diff

==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelLowering.cpp Tue May 27 19:24:25 2008
@@ -6324,6 +6324,11 @@
 
   // Transform it into VZEXT_LOAD addr.
   LoadSDNode *LD = cast<LoadSDNode>(Base);
+  
+  // Load must not be an extload.
+  if (LD->getExtensionType() != ISD::NON_EXTLOAD)
+    return SDOperand();
+  
   return DAG.getNode(X86ISD::VZEXT_LOAD, VT, LD->getChain(), LD->getBasePtr());
 }