[llvm-commits] [llvm] r51476 - in /llvm/trunk: lib/Transforms/Scalar/InstructionCombining.cpp test/Transforms/InstCombine/2008-05-22-NegValVector.ll

[Nick Lewycky]

Author: nicholas
Date: Thu May 22 23:54:45 2008
New Revision: 51476

URL: http://llvm.org/viewvc/llvm-project?rev=51476&view=rev
Log:
Constant integer vectors may also be negated.

Added:
    llvm/trunk/test/Transforms/InstCombine/2008-05-22-NegValVector.ll
Modified:
    llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp

Modified: llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp?rev=51476&r1=51475&r2=51476&view=diff

==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp Thu May 22 23:54:45 2008
@@ -550,6 +550,11 @@
   // Constants can be considered to be negated values if they can be folded.
   if (ConstantInt *C = dyn_cast<ConstantInt>(V))
     return ConstantExpr::getNeg(C);
+
+  if (ConstantVector *C = dyn_cast<ConstantVector>(V))
+    if (C->getType()->getElementType()->isInteger())
+      return ConstantExpr::getNeg(C);
+
   return 0;
 }
 

Added: llvm/trunk/test/Transforms/InstCombine/2008-05-22-NegValVector.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/InstCombine/2008-05-22-NegValVector.ll?rev=51476&view=auto

==============================================================================
--- llvm/trunk/test/Transforms/InstCombine/2008-05-22-NegValVector.ll (added)
+++ llvm/trunk/test/Transforms/InstCombine/2008-05-22-NegValVector.ll Thu May 22 23:54:45 2008
@@ -0,0 +1,8 @@
+; RUN: llvm-as < %s | opt -instcombine | llvm-dis | not grep sub
+
+define <3 x i8> @f(<3 x i8> %a) {
+  %A = sub <3 x i8> zeroinitializer, %a
+  %B = mul <3 x i8> %A, <i8 5, i8 5, i8 5>
+  ret <3 x i8> %B
+}
+