diff options
| -rw-r--r-- | llvm/lib/Transforms/Scalar/SCCP.cpp | 7 | ||||
| -rw-r--r-- | llvm/test/Transforms/IPConstantProp/noinline-return.ll | 21 |
2 files changed, 27 insertions, 1 deletions
diff --git a/llvm/lib/Transforms/Scalar/SCCP.cpp b/llvm/lib/Transforms/Scalar/SCCP.cpp index dd1123fd4fa..054ad712d38 100644 --- a/llvm/lib/Transforms/Scalar/SCCP.cpp +++ b/llvm/lib/Transforms/Scalar/SCCP.cpp @@ -1715,7 +1715,12 @@ static bool runIPSCCP(Module &M, const DataLayout &DL, // Don't touch naked functions. They may contain asm returning a // value we don't see, so we may end up interprocedurally propagating // the return value incorrectly. - if (F.hasExactDefinition() && !F.hasFnAttribute(Attribute::Naked)) + // Also, don't touch functions marked as noinline. Trivial functions may + // essentially be inlined because of return value propagation. + // (e.g. int tinkywinky(void) { return 666; }) + if (F.hasExactDefinition() && + !(F.hasFnAttribute(Attribute::Naked) || + F.hasFnAttribute(Attribute::NoInline))) Solver.AddTrackedFunction(&F); // If this function only has direct calls that we can see, we can track its diff --git a/llvm/test/Transforms/IPConstantProp/noinline-return.ll b/llvm/test/Transforms/IPConstantProp/noinline-return.ll new file mode 100644 index 00000000000..10950327327 --- /dev/null +++ b/llvm/test/Transforms/IPConstantProp/noinline-return.ll @@ -0,0 +1,21 @@ +; RUN: opt %s -ipsccp -S | FileCheck %s + +define i32 @tinkywinky() #0 { +entry: + ret i32 5 +} + +define i32 @patatino() { +entry: + %call = call i32 @tinkywinky() + +; Check that we don't propagate the return value of +; @tinkywinky. +; CHECK: call i32 @dipsy(i32 %call) + %call1 = call i32 @dipsy(i32 %call) + ret i32 %call1 +} + +declare i32 @dipsy(i32) + +attributes #0 = { noinline } |
