[llvm] r267773 - [X86]: Quit promoting 16 bit loads to 32 bit.

[Kevin B. Smith via llvm-commits]

Author: kbsmith1
Date: Wed Apr 27 14:58:03 2016
New Revision: 267773

URL: http://llvm.org/viewvc/llvm-project?rev=267773&view=rev
Log:
[X86]: Quit promoting 16 bit loads to 32 bit.
Differential Revision: http://reviews.llvm.org/D19592

Modified:
    llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
    llvm/trunk/test/CodeGen/X86/half.ll

Modified: llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelLowering.cpp?rev=267773&r1=267772&r2=267773&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelLowering.cpp Wed Apr 27 14:58:03 2016
@@ -29639,23 +29639,6 @@ bool X86TargetLowering::IsDesirableToPro
   bool Commute = false;
   switch (Op.getOpcode()) {
   default: break;
-  case ISD::LOAD: {
-    LoadSDNode *LD = cast<LoadSDNode>(Op);
-    // If the non-extending load has a single use and it's not live out, then it
-    // might be folded.
-    if (LD->getExtensionType() == ISD::NON_EXTLOAD /*&&
-                                                     Op.hasOneUse()*/) {
-      for (SDNode::use_iterator UI = Op.getNode()->use_begin(),
-             UE = Op.getNode()->use_end(); UI != UE; ++UI) {
-        // The only case where we'd want to promote LOAD (rather then it being
-        // promoted as an operand is when it's only use is liveout.
-        if (UI->getOpcode() != ISD::CopyToReg)
-          return false;
-      }
-    }
-    Promote = true;
-    break;
-  }
   case ISD::SIGN_EXTEND:
   case ISD::ZERO_EXTEND:
   case ISD::ANY_EXTEND:

Modified: llvm/trunk/test/CodeGen/X86/half.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/half.ll?rev=267773&r1=267772&r2=267773&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/half.ll (original)
+++ llvm/trunk/test/CodeGen/X86/half.ll Wed Apr 27 14:58:03 2016
@@ -19,7 +19,8 @@ define void @test_load_store(half* %in,
 
 define i16 @test_bitcast_from_half(half* %addr) {
 ; CHECK-LABEL: test_bitcast_from_half:
-; CHECK: movzwl (%rdi), %eax
+; BWON:  movzwl (%rdi), %eax
+; BWOFF: movw (%rdi), %ax
   %val = load half, half* %addr
   %val_int = bitcast half %val to i16
   ret i16 %val_int