diff --git a/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp b/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp --- a/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp +++ b/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp @@ -1360,6 +1360,18 @@ if (Inverted) return false; + auto *ARTy = LHSS->getType(); + auto *MaxIterTy = MaxIter->getType(); + // If possible, adjust types. + if (SE->getTypeSizeInBits(ARTy) > SE->getTypeSizeInBits(MaxIterTy)) + MaxIter = SE->getZeroExtendExpr(MaxIter, ARTy); + else if (SE->getTypeSizeInBits(ARTy) < SE->getTypeSizeInBits(MaxIterTy)) { + const SCEV *MinusOne = SE->getMinusOne(ARTy); + auto *MaxAllowedIter = SE->getZeroExtendExpr(MinusOne, MaxIterTy); + if (SE->isKnownPredicateAt(ICmpInst::ICMP_ULE, MaxIter, MaxAllowedIter, BI)) + MaxIter = SE->getTruncateExpr(MaxIter, ARTy); + } + if (SkipLastIter) { const SCEV *One = SE->getOne(MaxIter->getType()); MaxIter = SE->getMinusSCEV(MaxIter, One); diff --git a/llvm/test/Transforms/IndVarSimplify/predicated_ranges.ll b/llvm/test/Transforms/IndVarSimplify/predicated_ranges.ll --- a/llvm/test/Transforms/IndVarSimplify/predicated_ranges.ll +++ b/llvm/test/Transforms/IndVarSimplify/predicated_ranges.ll @@ -624,6 +624,7 @@ ; CHECK-NEXT: preheader: ; CHECK-NEXT: [[LEN:%.*]] = load i32, i32* [[P:%.*]], align 4 ; CHECK-NEXT: [[START:%.*]] = zext i32 [[LEN]] to i64 +; CHECK-NEXT: [[TMP0:%.*]] = add i32 [[LEN]], -1 ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[IV:%.*]] = phi i64 [ [[START]], [[PREHEADER:%.*]] ], [ [[IV_NEXT:%.*]], [[BACKEDGE:%.*]] ] @@ -631,9 +632,8 @@ ; CHECK-NEXT: br i1 [[ZERO_COND]], label [[EXIT:%.*]], label [[RANGE_CHECK_BLOCK:%.*]] ; CHECK: range_check_block: ; CHECK-NEXT: [[IV_NEXT]] = sub nsw i64 [[IV]], 1 -; CHECK-NEXT: [[NARROW:%.*]] = trunc i64 [[IV_NEXT]] to i32 -; CHECK-NEXT: [[RANGE_CHECK:%.*]] = icmp ult i32 [[NARROW]], [[LEN]] -; CHECK-NEXT: br i1 [[RANGE_CHECK]], label [[BACKEDGE]], label [[FAIL:%.*]] +; CHECK-NEXT: [[RANGE_CHECK1:%.*]] = icmp ult i32 [[TMP0]], [[LEN]] +; CHECK-NEXT: br i1 [[RANGE_CHECK1]], label [[BACKEDGE]], label [[FAIL:%.*]] ; CHECK: backedge: ; CHECK-NEXT: [[EL_PTR:%.*]] = getelementptr i32, i32* [[ARR:%.*]], i64 [[IV]] ; CHECK-NEXT: [[EL:%.*]] = load i32, i32* [[EL_PTR]], align 4 @@ -678,6 +678,7 @@ ; CHECK-NEXT: preheader: ; CHECK-NEXT: [[LEN:%.*]] = load i32, i32* [[P:%.*]], align 4 ; CHECK-NEXT: [[START:%.*]] = zext i32 [[LEN]] to i64 +; CHECK-NEXT: [[TMP0:%.*]] = add i32 [[LEN]], -1 ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[IV:%.*]] = phi i64 [ [[START]], [[PREHEADER:%.*]] ], [ [[IV_NEXT:%.*]], [[BACKEDGE:%.*]] ] @@ -685,9 +686,8 @@ ; CHECK-NEXT: br i1 [[ZERO_COND]], label [[EXIT:%.*]], label [[RANGE_CHECK_BLOCK:%.*]] ; CHECK: range_check_block: ; CHECK-NEXT: [[IV_NEXT]] = sub nsw i64 [[IV]], 1 -; CHECK-NEXT: [[NARROW:%.*]] = trunc i64 [[IV_NEXT]] to i32 -; CHECK-NEXT: [[RANGE_CHECK:%.*]] = icmp uge i32 [[NARROW]], [[LEN]] -; CHECK-NEXT: br i1 [[RANGE_CHECK]], label [[FAIL:%.*]], label [[BACKEDGE]] +; CHECK-NEXT: [[RANGE_CHECK1:%.*]] = icmp uge i32 [[TMP0]], [[LEN]] +; CHECK-NEXT: br i1 [[RANGE_CHECK1]], label [[FAIL:%.*]], label [[BACKEDGE]] ; CHECK: backedge: ; CHECK-NEXT: [[EL_PTR:%.*]] = getelementptr i32, i32* [[ARR:%.*]], i64 [[IV]] ; CHECK-NEXT: [[EL:%.*]] = load i32, i32* [[EL_PTR]], align 4