add ShouldChangeType() variant that takes bitwidths
This is more efficient for cases like D12965 where we already have widths.
llvm-svn: 248170
diff --git a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
index 8c70a1c..72548dc 100644
--- a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -80,14 +80,12 @@
return llvm::EmitGEPOffset(Builder, DL, GEP);
}
-/// Return true if it is desirable to convert a computation from 'From' to 'To'.
+/// Return true if it is desirable to convert an integer computation from a
+/// given bit width to a new bit width.
/// We don't want to convert from a legal to an illegal type for example or from
/// a smaller to a larger illegal type.
-bool InstCombiner::ShouldChangeType(Type *From, Type *To) const {
- assert(From->isIntegerTy() && To->isIntegerTy());
-
- unsigned FromWidth = From->getPrimitiveSizeInBits();
- unsigned ToWidth = To->getPrimitiveSizeInBits();
+bool InstCombiner::ShouldChangeType(unsigned FromWidth,
+ unsigned ToWidth) const {
bool FromLegal = DL.isLegalInteger(FromWidth);
bool ToLegal = DL.isLegalInteger(ToWidth);
@@ -104,6 +102,17 @@
return true;
}
+/// Return true if it is desirable to convert a computation from 'From' to 'To'.
+/// We don't want to convert from a legal to an illegal type for example or from
+/// a smaller to a larger illegal type.
+bool InstCombiner::ShouldChangeType(Type *From, Type *To) const {
+ assert(From->isIntegerTy() && To->isIntegerTy());
+
+ unsigned FromWidth = From->getPrimitiveSizeInBits();
+ unsigned ToWidth = To->getPrimitiveSizeInBits();
+ return ShouldChangeType(FromWidth, ToWidth);
+}
+
// Return true, if No Signed Wrap should be maintained for I.
// The No Signed Wrap flag can be kept if the operation "B (I.getOpcode) C",
// where both B and C should be ConstantInts, results in a constant that does