///
unsigned FunctionNumber;
- /// The alignment of the function.
+ /// Alignment - The alignment of the function.
unsigned Alignment;
+ /// CallsSetJmp - True if the function calls setjmp or sigsetjmp. This is used
+ /// to limit optimizations which cannot reason about the control flow of
+ /// setjmp.
+ bool CallsSetJmp;
+
MachineFunction(const MachineFunction &); // DO NOT IMPLEMENT
void operator=(const MachineFunction&); // DO NOT IMPLEMENT
public:
void EnsureAlignment(unsigned A) {
if (Alignment < A) Alignment = A;
}
+
+ /// callsSetJmp - Returns true if the function calls setjmp or sigsetjmp.
+ bool callsSetJmp() const {
+ return CallsSetJmp;
+ }
+
+ /// setCallsSetJmp - Set a flag that indicates if there's a call to setjmp or
+ /// sigsetjmp.
+ void setCallsSetJmp(bool B) {
+ CallsSetJmp = B;
+ }
/// getInfo - Keep track of various per-function pieces of information for
/// backends that would like to do so.
#include "llvm/Intrinsics.h"
#include "llvm/IntrinsicInst.h"
#include "llvm/LLVMContext.h"
+#include "llvm/Module.h"
#include "llvm/CodeGen/FastISel.h"
#include "llvm/CodeGen/GCStrategy.h"
#include "llvm/CodeGen/GCMetadata.h"
MachineFunctionPass::getAnalysisUsage(AU);
}
+/// FunctionCallsSetJmp - Return true if the function has a call to setjmp or
+/// sigsetjmp. This is used to limit code-gen optimizations on the machine
+/// function.
+static bool FunctionCallsSetJmp(const Function *F) {
+ const Module *M = F->getParent();
+ const Function *SetJmp = M->getFunction("setjmp");
+ const Function *SigSetJmp = M->getFunction("sigsetjmp");
+
+ if (!SetJmp && !SigSetJmp)
+ return false;
+
+ if (SetJmp && !SetJmp->use_empty())
+ for (Value::const_use_iterator
+ I = SetJmp->use_begin(), E = SetJmp->use_end(); I != E; ++I)
+ if (const CallInst *CI = dyn_cast<CallInst>(I))
+ if (CI->getParent()->getParent() == F)
+ return true;
+
+ if (SigSetJmp && !SigSetJmp->use_empty())
+ for (Value::const_use_iterator
+ I = SigSetJmp->use_begin(), E = SigSetJmp->use_end(); I != E; ++I)
+ if (const CallInst *CI = dyn_cast<CallInst>(I))
+ if (CI->getParent()->getParent() == F)
+ return true;
+
+ return false;
+}
+
bool SelectionDAGISel::runOnMachineFunction(MachineFunction &mf) {
// Do some sanity-checking on the command-line options.
assert((!EnableFastISelVerbose || EnableFastISel) &&
done:;
}
+ // Determine if there is a call to setjmp in the machine function.
+ MF->setCallsSetJmp(FunctionCallsSetJmp(&Fn));
+
// Release function-specific state. SDB and CurDAG are already cleared
// at this point.
FuncInfo->clear();
};
}
-/// CheckForSetJmpCall - Return true if there's a call to setjmp/sigsetjmp in
-/// this function.
-bool StackSlotColoring::CheckForSetJmpCall(const MachineFunction &MF) const {
- const Function *F = MF.getFunction();
- const Module *M = F->getParent();
- const Function *SetJmp = M->getFunction("setjmp");
- const Function *SigSetJmp = M->getFunction("sigsetjmp");
-
- if (!SetJmp && !SigSetJmp)
- return false;
-
- if (SetJmp && !SetJmp->use_empty())
- for (Value::const_use_iterator
- I = SetJmp->use_begin(), E = SetJmp->use_end(); I != E; ++I)
- if (const CallInst *CI = dyn_cast<CallInst>(I))
- if (CI->getParent()->getParent() == F)
- return true;
-
- if (SigSetJmp && !SigSetJmp->use_empty())
- for (Value::const_use_iterator
- I = SigSetJmp->use_begin(), E = SigSetJmp->use_end(); I != E; ++I)
- if (const CallInst *CI = dyn_cast<CallInst>(I))
- if (CI->getParent()->getParent() == F)
- return true;
-
- return false;
-}
-
/// ScanForSpillSlotRefs - Scan all the machine instructions for spill slot
/// references and update spill slot weights.
void StackSlotColoring::ScanForSpillSlotRefs(MachineFunction &MF) {
// coloring. The stack could be modified before the longjmp is executed,
// resulting in the wrong value being used afterwards. (See
// <rdar://problem/8007500>.)
- //
- // FIXME: This goes beyond the setjmp/sigsetjmp functions. Ideally, we should
- // check for the GCC "returns twice" attribute.
- if (CheckForSetJmpCall(MF))
+ if (MF.callsSetJmp())
return false;
// Gather spill slot references