[llvm] r220664 - InstCombine: Fix a combine assuming that icmp operands were integers

[David Majnemer]

Author: majnemer
Date: Mon Oct 27 00:47:49 2014
New Revision: 220664

URL: http://llvm.org/viewvc/llvm-project?rev=220664&view=rev
Log:
InstCombine: Fix a combine assuming that icmp operands were integers

An icmp may have pointer arguments, it isn't limited to integers or
vectors of integers.

This fixes PR21388.

Modified:
    llvm/trunk/lib/Transforms/InstCombine/InstCombineCasts.cpp
    llvm/trunk/test/Transforms/InstCombine/cast.ll

Modified: llvm/trunk/lib/Transforms/InstCombine/InstCombineCasts.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstCombineCasts.cpp?rev=220664&r1=220663&r2=220664&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstCombineCasts.cpp (original)
+++ llvm/trunk/lib/Transforms/InstCombine/InstCombineCasts.cpp Mon Oct 27 00:47:49 2014
@@ -900,6 +900,10 @@ Instruction *InstCombiner::transformSExt
   Value *Op0 = ICI->getOperand(0), *Op1 = ICI->getOperand(1);
   ICmpInst::Predicate Pred = ICI->getPredicate();
 
+  // Don't bother if Op1 isn't of vector or integer type.
+  if (!Op1->getType()->isIntOrIntVectorTy())
+    return nullptr;
+
   if (Constant *Op1C = dyn_cast<Constant>(Op1)) {
     // (x <s  0) ? -1 : 0 -> ashr x, 31        -> all ones if negative
     // (x >s -1) ? -1 : 0 -> not (ashr x, 31)  -> all ones if positive

Modified: llvm/trunk/test/Transforms/InstCombine/cast.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/InstCombine/cast.ll?rev=220664&r1=220663&r2=220664&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/InstCombine/cast.ll (original)
+++ llvm/trunk/test/Transforms/InstCombine/cast.ll Mon Oct 27 00:47:49 2014
@@ -1084,3 +1084,12 @@ define float @overflow_sitofp() {
 ; CHECK-NEXT: ret float undef 
 }
 
+define i32 @PR21388(i32* %v) {
+  %icmp = icmp slt i32* %v, null
+  %sext = sext i1 %icmp to i32
+  ret i32 %sext
+; CHECK-LABEL: @PR21388(
+; CHECK-NEXT: %[[icmp:.*]] = icmp slt i32* %v, null
+; CHECK-NEXT: %[[sext:.*]] = sext i1 %[[icmp]] to i32
+; CHECK-NEXT: ret i32 %[[sext]]
+}