[ValueTracking,VectorCombine] Allow passing DT to computeConstantRange.

isValidAssumeForContext can provide better results with access to the
dominator tree in some cases. This patch adjusts computeConstantRange to
allow passing through a dominator tree.

The use VectorCombine is updated to pass through the DT to enable
additional scalarization.

Note that similar APIs like computeKnownBits already accept optional dominator
tree arguments.

Reviewed By: lebedev.ri

Differential Revision: https://reviews.llvm.org/D110175

1 files changed, 3 insertions, 2 deletions

diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp
index 57869e3..d381ee2 100644
--- a/llvm/lib/Analysis/ValueTracking.cpp
+++ b/llvm/lib/Analysis/ValueTracking.cpp
@@ -7031,6 +7031,7 @@ static void setLimitsForSelectPattern(const SelectInst &SI, APInt &Lower,
 ConstantRange llvm::computeConstantRange(const Value *V, bool UseInstrInfo,
                                          AssumptionCache *AC,
                                          const Instruction *CtxI,
+                                         const DominatorTree *DT,
                                          unsigned Depth) {
   assert(V->getType()->isIntOrIntVectorTy() && "Expected integer instruction");
 
@@ -7069,7 +7070,7 @@ ConstantRange llvm::computeConstantRange(const Value *V, bool UseInstrInfo,
       assert(I->getCalledFunction()->getIntrinsicID() == Intrinsic::assume &&
              "must be an assume intrinsic");
 
-      if (!isValidAssumeForContext(I, CtxI, nullptr))
+      if (!isValidAssumeForContext(I, CtxI, DT))
         continue;
       Value *Arg = I->getArgOperand(0);
       ICmpInst *Cmp = dyn_cast<ICmpInst>(Arg);
@@ -7077,7 +7078,7 @@ ConstantRange llvm::computeConstantRange(const Value *V, bool UseInstrInfo,
       if (!Cmp || Cmp->getOperand(0) != V)
         continue;
       ConstantRange RHS = computeConstantRange(Cmp->getOperand(1), UseInstrInfo,
-                                               AC, I, Depth + 1);
+                                               AC, I, DT, Depth + 1);
       CR = CR.intersectWith(
           ConstantRange::makeAllowedICmpRegion(Cmp->getPredicate(), RHS));
     }