[PATCH] use an integer constant for FABS / FNEG (x86)

[David Majnemer]

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Comment at: lib/Target/X86/X86ISelLowering.cpp:12124
@@ -12129,1 +12123,3 @@
+  unsigned EltBits = EltVT.getSizeInBits();
+  Constant *C = ConstantInt::get(*Context, ~APInt::getSignBit(EltBits));
   C = ConstantVector::getSplat(NumElts, C);
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I think you can replace `~APInt::getSignBit(EltBits)` with `APInt::getSignedMaxValue(EltBits)`

http://reviews.llvm.org/D5052