[ConstantRange] Add getFull() + getEmpty() named constructors; NFC
This adds ConstantRange::getFull(BitWidth) and
ConstantRange::getEmpty(BitWidth) named constructors as more readable
alternatives to the current ConstantRange(BitWidth, /* full */ false)
and similar. Additionally private getFull() and getEmpty() member
functions are added which return a full/empty range with the same bit
width -- these are commonly needed inside ConstantRange.cpp.
The IsFullSet argument in the ConstantRange(BitWidth, IsFullSet)
constructor is now mandatory for the few usages that still make use of it.
Differential Revision: https://reviews.llvm.org/D59716
llvm-svn: 356852
diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp
index 4c2e7f2..d3cbd07 100644
--- a/llvm/lib/Analysis/ValueTracking.cpp
+++ b/llvm/lib/Analysis/ValueTracking.cpp
@@ -5711,7 +5711,7 @@
setLimitsForSelectPattern(*SI, Lower, Upper);
ConstantRange CR = Lower != Upper ? ConstantRange(Lower, Upper)
- : ConstantRange(BitWidth, true);
+ : ConstantRange::getFull(BitWidth);
if (auto *I = dyn_cast<Instruction>(V))
if (auto *Range = IIQ.getMetadata(I, LLVMContext::MD_range))