[llvm] 4a3e006 - [LVI] Use range metadata on intrinsics

[Nikita Popov via llvm-commits]

Author: Nikita Popov
Date: 2021-04-02T16:45:31+02:00
New Revision: 4a3e006830aaaf094f3a8ea0a3780a5e1b6f3ecc

URL: https://github.com/llvm/llvm-project/commit/4a3e006830aaaf094f3a8ea0a3780a5e1b6f3ecc
DIFF: https://github.com/llvm/llvm-project/commit/4a3e006830aaaf094f3a8ea0a3780a5e1b6f3ecc.diff

LOG: [LVI] Use range metadata on intrinsics

If we don't know how to handle an intrinsic, we should still
make use of normal call range metadata.

Added: 
    

Modified: 
    llvm/lib/Analysis/LazyValueInfo.cpp
    llvm/test/Transforms/CorrelatedValuePropagation/range.ll

Removed: 
    


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diff  --git a/llvm/lib/Analysis/LazyValueInfo.cpp b/llvm/lib/Analysis/LazyValueInfo.cpp
index 8d807c3331ea..c1a8d3d25bf5 100644
--- a/llvm/lib/Analysis/LazyValueInfo.cpp
+++ b/llvm/lib/Analysis/LazyValueInfo.cpp
@@ -1000,8 +1000,8 @@ Optional<ValueLatticeElement> LazyValueInfoImpl::solveBlockValueIntrinsic(
     IntrinsicInst *II, BasicBlock *BB) {
   if (!ConstantRange::isIntrinsicSupported(II->getIntrinsicID())) {
     LLVM_DEBUG(dbgs() << " compute BB '" << BB->getName()
-                      << "' - overdefined (unknown intrinsic).\n");
-    return ValueLatticeElement::getOverdefined();
+                      << "' - unknown intrinsic.\n");
+    return getFromRangeMetadata(II);
   }
 
   SmallVector<ConstantRange, 2> OpRanges;

diff  --git a/llvm/test/Transforms/CorrelatedValuePropagation/range.ll b/llvm/test/Transforms/CorrelatedValuePropagation/range.ll
index 356c4b890420..89bcf9fd15f5 100644
--- a/llvm/test/Transforms/CorrelatedValuePropagation/range.ll
+++ b/llvm/test/Transforms/CorrelatedValuePropagation/range.ll
@@ -938,8 +938,7 @@ define i1 @intrinsic_range(i16 %x) {
 ; CHECK-LABEL: @intrinsic_range(
 ; CHECK-NEXT:    [[CTLZ:%.*]] = call i16 @llvm.ctlz.i16(i16 [[X:%.*]], i1 false), !range [[RNG5:![0-9]+]]
 ; CHECK-NEXT:    [[TRUNC:%.*]] = trunc i16 [[CTLZ]] to i8
-; CHECK-NEXT:    [[RES:%.*]] = icmp ult i8 [[TRUNC]], 8
-; CHECK-NEXT:    ret i1 [[RES]]
+; CHECK-NEXT:    ret i1 true
 ;
   %ctlz = call i16 @llvm.ctlz.i16(i16 %x, i1 false), !range !{i16 0, i16 8}
   %trunc = trunc i16 %ctlz to i8