[PATCH] D12703: [InstCombine] Optimize icmp slt signum(x), 1 --> icmp sle x, 0.

[David Majnemer via llvm-commits]

majnemer added inline comments.

================
Comment at: include/llvm/IR/PatternMatch.h:1281-1284
@@ +1280,6 @@
+    Type *Ty = V->getType();
+    if (!isa<IntegerType>(Ty))
+      return false;
+
+    unsigned ShiftWidth = cast<IntegerType>(Ty)->getBitWidth() - 1;
+    Value *OpL = nullptr, *OpR = nullptr;
----------------
Could you use `getScalarSizeInBits`? My thinking is that this would enable the transform to hack on vectors of integers.  The only caveat is that you need to fail if it gives you back zero, this could happen if its a vector of pointers.


http://reviews.llvm.org/D12703