From 9a6b9bffa53bfa5e1a8373b31b2ddfa7b6bd7b30 Mon Sep 17 00:00:00 2001 From: Quentin Colombet Date: Fri, 7 Jun 2013 20:18:12 +0000 Subject: Add a backend option to warn on a given stack size limit. Option: -mllvm -warn-stack-size= Output (if limit is exceeded): warning: Stack size limit exceeded () in . The longer term plan is to hook that to a clang warning. PR:4072 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183552 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/PrologEpilogInserter.cpp | 13 +++++++++++++ test/CodeGen/ARM/warn-stack.ll | 24 ++++++++++++++++++++++++ test/CodeGen/X86/warn-stack.ll | 24 ++++++++++++++++++++++++ 3 files changed, 61 insertions(+) create mode 100644 test/CodeGen/ARM/warn-stack.ll create mode 100644 test/CodeGen/X86/warn-stack.ll diff --git a/lib/CodeGen/PrologEpilogInserter.cpp b/lib/CodeGen/PrologEpilogInserter.cpp index 959dd7df58..3a77af0cc4 100644 --- a/lib/CodeGen/PrologEpilogInserter.cpp +++ b/lib/CodeGen/PrologEpilogInserter.cpp @@ -35,6 +35,7 @@ #include "llvm/Support/CommandLine.h" #include "llvm/Support/Compiler.h" #include "llvm/Support/Debug.h" +#include "llvm/Support/raw_ostream.h" #include "llvm/Target/TargetFrameLowering.h" #include "llvm/Target/TargetInstrInfo.h" #include "llvm/Target/TargetMachine.h" @@ -46,6 +47,11 @@ using namespace llvm; char PEI::ID = 0; char &llvm::PrologEpilogCodeInserterID = PEI::ID; +static cl::opt +WarnStackSize("warn-stack-size", cl::Hidden, + cl::desc("Warn for stack size bigger than the given" + " number")); + INITIALIZE_PASS_BEGIN(PEI, "prologepilog", "Prologue/Epilogue Insertion", false, false) INITIALIZE_PASS_DEPENDENCY(MachineLoopInfo) @@ -128,6 +134,13 @@ bool PEI::runOnMachineFunction(MachineFunction &Fn) { // Clear any vregs created by virtual scavenging. Fn.getRegInfo().clearVirtRegs(); + // Warn on stack size when we exceeds the given limit. + MachineFrameInfo *MFI = Fn.getFrameInfo(); + if (WarnStackSize.getNumOccurrences() > 0 && + WarnStackSize < MFI->getStackSize()) + errs() << "warning: Stack size limit exceeded (" << MFI->getStackSize() + << ") in " << Fn.getName() << ".\n"; + delete RS; clearAllSets(); return true; diff --git a/test/CodeGen/ARM/warn-stack.ll b/test/CodeGen/ARM/warn-stack.ll new file mode 100644 index 0000000000..4ddc846dc7 --- /dev/null +++ b/test/CodeGen/ARM/warn-stack.ll @@ -0,0 +1,24 @@ +; RUN: llc -march arm -warn-stack-size=80 < %s 2>&1 >/dev/null | FileCheck %s +; Check the internal option that warns when the stack size exceeds the +; given amount. +; + +; CHECK-NOT: nowarn +define void @nowarn() nounwind ssp { +entry: + %buffer = alloca [12 x i8], align 1 + %arraydecay = getelementptr inbounds [12 x i8]* %buffer, i64 0, i64 0 + call void @doit(i8* %arraydecay) nounwind + ret void +} + +; CHECK: warning: Stack size limit exceeded (92) in warn. +define void @warn() nounwind ssp { +entry: + %buffer = alloca [80 x i8], align 1 + %arraydecay = getelementptr inbounds [80 x i8]* %buffer, i64 0, i64 0 + call void @doit(i8* %arraydecay) nounwind + ret void +} + +declare void @doit(i8*) diff --git a/test/CodeGen/X86/warn-stack.ll b/test/CodeGen/X86/warn-stack.ll new file mode 100644 index 0000000000..0a6a506c7a --- /dev/null +++ b/test/CodeGen/X86/warn-stack.ll @@ -0,0 +1,24 @@ +; RUN: llc -march x86 -warn-stack-size=80 < %s 2>&1 >/dev/null | FileCheck %s +; Check the internal option that warns when the stack size exceeds the +; given amount. +; + +; CHECK-NOT: nowarn +define void @nowarn() nounwind ssp { +entry: + %buffer = alloca [12 x i8], align 1 + %arraydecay = getelementptr inbounds [12 x i8]* %buffer, i64 0, i64 0 + call void @doit(i8* %arraydecay) nounwind + ret void +} + +; CHECK: warning: Stack size limit exceeded (92) in warn. +define void @warn() nounwind ssp { +entry: + %buffer = alloca [80 x i8], align 1 + %arraydecay = getelementptr inbounds [80 x i8]* %buffer, i64 0, i64 0 + call void @doit(i8* %arraydecay) nounwind + ret void +} + +declare void @doit(i8*) -- cgit v1.2.3