diff --git a/llvm/include/llvm/Transforms/IPO/IROutliner.h b/llvm/include/llvm/Transforms/IPO/IROutliner.h --- a/llvm/include/llvm/Transforms/IPO/IROutliner.h +++ b/llvm/include/llvm/Transforms/IPO/IROutliner.h @@ -367,6 +367,11 @@ Function *F = CI.getCalledFunction(); if (!F || CI.isIndirectCall() || !F->hasName()) return false; + // Returning twice can cause issues with the state of the function call + // that were not expected when the function was used, so we do not include + // the call in outlined functions. + if (CI.canReturnTwice()) + return false; return true; } // TODO: Handle FreezeInsts. Since a frozen value could be frozen inside diff --git a/llvm/test/Transforms/IROutliner/illegal-returns-twice.ll b/llvm/test/Transforms/IROutliner/illegal-returns-twice.ll new file mode 100644 --- /dev/null +++ b/llvm/test/Transforms/IROutliner/illegal-returns-twice.ll @@ -0,0 +1,66 @@ +; NOTE: Assertions have been autogenerated by utils/update_test_checks.py +; RUN: opt -S -verify -iroutliner -ir-outlining-no-cost < %s | FileCheck %s + +; This test checks that we do not outline functions that are marked as returns +; twice, since these can alter the frame of the function and affect how the +; outliner behaves, causing miscompiles. + +; Function Attrs: optsize returns_twice +declare i32 @setjmp(i32*) local_unnamed_addr #1 +@tmp_jmpb = global [37 x i32] zeroinitializer, align 16 + +define void @function1() { +; CHECK-LABEL: @function1( +; CHECK-NEXT: entry: +; CHECK-NEXT: [[A:%.*]] = alloca i32, align 4 +; CHECK-NEXT: [[B:%.*]] = alloca i32, align 4 +; CHECK-NEXT: [[C:%.*]] = alloca i32, align 4 +; CHECK-NEXT: store i32 2, i32* [[A]], align 4 +; CHECK-NEXT: store i32 3, i32* [[B]], align 4 +; CHECK-NEXT: store i32 4, i32* [[C]], align 4 +; CHECK-NEXT: [[CALL:%.*]] = call i32 @setjmp(i32* getelementptr inbounds ([37 x i32], [37 x i32]* @tmp_jmpb, i64 0, i64 0)) +; CHECK-NEXT: call void @outlined_ir_func_0(i32* [[A]], i32* [[B]], i32* [[C]]) +; CHECK-NEXT: ret void +; +entry: + %a = alloca i32, align 4 + %b = alloca i32, align 4 + %c = alloca i32, align 4 + store i32 2, i32* %a, align 4 + store i32 3, i32* %b, align 4 + store i32 4, i32* %c, align 4 + %call = call i32 @setjmp(i32* getelementptr inbounds ([37 x i32], [37 x i32]* @tmp_jmpb, i64 0, i64 0)) + %al = load i32, i32* %a + %bl = load i32, i32* %b + %cl = load i32, i32* %c + ret void +} + +define void @function2() { +; CHECK-LABEL: @function2( +; CHECK-NEXT: entry: +; CHECK-NEXT: [[A:%.*]] = alloca i32, align 4 +; CHECK-NEXT: [[B:%.*]] = alloca i32, align 4 +; CHECK-NEXT: [[C:%.*]] = alloca i32, align 4 +; CHECK-NEXT: store i32 2, i32* [[A]], align 4 +; CHECK-NEXT: store i32 3, i32* [[B]], align 4 +; CHECK-NEXT: store i32 4, i32* [[C]], align 4 +; CHECK-NEXT: [[CALL:%.*]] = call i32 @setjmp(i32* getelementptr inbounds ([37 x i32], [37 x i32]* @tmp_jmpb, i64 0, i64 0)) +; CHECK-NEXT: call void @outlined_ir_func_0(i32* [[A]], i32* [[B]], i32* [[C]]) +; CHECK-NEXT: ret void +; +entry: + %a = alloca i32, align 4 + %b = alloca i32, align 4 + %c = alloca i32, align 4 + store i32 2, i32* %a, align 4 + store i32 3, i32* %b, align 4 + store i32 4, i32* %c, align 4 + %call = call i32 @setjmp(i32* getelementptr inbounds ([37 x i32], [37 x i32]* @tmp_jmpb, i64 0, i64 0)) + %al = load i32, i32* %a + %bl = load i32, i32* %b + %cl = load i32, i32* %c + ret void +} + +attributes #1 = { optsize returns_twice }