From 9207e62438753d52de44170724a90a29ad58c119 Mon Sep 17 00:00:00 2001 From: Yingwei Zheng Date: Fri, 11 Apr 2025 00:17:51 +0800 Subject: [PATCH 1/2] [IndVarSimplify] Add pre-commit tests. NFC. --- .../Transforms/IndVarSimplify/pr135182.ll | 27 +++++++++++++++++++ 1 file changed, 27 insertions(+) create mode 100644 llvm/test/Transforms/IndVarSimplify/pr135182.ll diff --git a/llvm/test/Transforms/IndVarSimplify/pr135182.ll b/llvm/test/Transforms/IndVarSimplify/pr135182.ll new file mode 100644 index 0000000000000..48607ea92d523 --- /dev/null +++ b/llvm/test/Transforms/IndVarSimplify/pr135182.ll @@ -0,0 +1,27 @@ +; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5 +; RUN: opt -S -passes=indvars < %s | FileCheck %s + +target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128" + +define i32 @pr135182() { +; CHECK-LABEL: define i32 @pr135182() { +; CHECK-NEXT: [[ENTRY:.*:]] +; CHECK-NEXT: br label %[[FOR_BODY:.*]] +; CHECK: [[FOR_BODY]]: +; CHECK-NEXT: br i1 false, label %[[FOR_BODY]], label %[[FOR_END:.*]] +; CHECK: [[FOR_END]]: +; CHECK-NEXT: ret i32 131048 +; +entry: + br label %for.body + +for.body: + %indvar = phi i16 [ -12, %entry ], [ %indvar.next, %for.body ] + %add = add i16 %indvar, %indvar + %ext = zext i16 %add to i32 + %indvar.next = add i16 %indvar, 1 + br i1 false, label %for.body, label %for.end + +for.end: + ret i32 %ext +} From dc3c046068762df3c5b24da8d52fa671cb04f582 Mon Sep 17 00:00:00 2001 From: Yingwei Zheng Date: Fri, 11 Apr 2025 00:34:13 +0800 Subject: [PATCH 2/2] [IndVarSimplify] Handle the case where both operands are the same when widening IV --- llvm/lib/Transforms/Utils/SimplifyIndVar.cpp | 3 +++ llvm/test/Transforms/IndVarSimplify/pr135182.ll | 2 +- 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/llvm/lib/Transforms/Utils/SimplifyIndVar.cpp b/llvm/lib/Transforms/Utils/SimplifyIndVar.cpp index 7b9c5c77cbe98..5a76bec017655 100644 --- a/llvm/lib/Transforms/Utils/SimplifyIndVar.cpp +++ b/llvm/lib/Transforms/Utils/SimplifyIndVar.cpp @@ -1743,6 +1743,9 @@ bool WidenIV::widenWithVariantUse(WidenIV::NarrowIVDefUse DU) { // TODO: Support case for NarrowDef = NarrowUse->getOperand(1). if (NarrowUse->getOperand(0) != NarrowDef) return false; + // We cannot use a different extend kind for the same operand. + if (NarrowUse->getOperand(1) == NarrowDef) + return false; if (!SE->isKnownNegative(RHS)) return false; bool ProvedSubNUW = SE->isKnownPredicateAt(ICmpInst::ICMP_UGE, LHS, diff --git a/llvm/test/Transforms/IndVarSimplify/pr135182.ll b/llvm/test/Transforms/IndVarSimplify/pr135182.ll index 48607ea92d523..1db96872cffc4 100644 --- a/llvm/test/Transforms/IndVarSimplify/pr135182.ll +++ b/llvm/test/Transforms/IndVarSimplify/pr135182.ll @@ -10,7 +10,7 @@ define i32 @pr135182() { ; CHECK: [[FOR_BODY]]: ; CHECK-NEXT: br i1 false, label %[[FOR_BODY]], label %[[FOR_END:.*]] ; CHECK: [[FOR_END]]: -; CHECK-NEXT: ret i32 131048 +; CHECK-NEXT: ret i32 65512 ; entry: br label %for.body