replica
/
hanchenye-llvm-project
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Remove the last remnants of the Obj-C EH stack code. 

llvm-svn: 64205
This commit is contained in:
Anders Carlsson 2009-02-10 06:07:49 +00:00
parent 9b6c1d6313
commit 33c1b6528f
4 changed files with 4 additions and 220 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

30
clang/lib/CodeGen/CGObjCMac.cpp
View File

@ -2086,36 +2086,6 @@ void CGObjCMac::EmitThrowStmt(CodeGen::CodeGenFunction &CGF,
CGF.Builder.ClearInsertionPoint();
}
void CodeGenFunction::EmitJumpThroughFinally(llvm::BasicBlock *Dest) {
EmitJumpThroughFinally(ObjCEHStack.back(), Dest);
}
void CodeGenFunction::EmitJumpThroughFinally(ObjCEHEntry *E,
llvm::BasicBlock *Dst) {
if (!HaveInsertPoint())
return;
// Find the destination code for this block. We always use 0 for the
// fallthrough block (default destination).
llvm::SwitchInst *SI = E->FinallySwitch;
llvm::ConstantInt *ID;
if (Dst == SI->getDefaultDest()) {
ID = llvm::ConstantInt::get(llvm::Type::Int32Ty, 0);
} else {
ID = SI->findCaseDest(Dst);
if (!ID) {
// No code found, get a new unique one by just using the number
// of switch successors.
ID = llvm::ConstantInt::get(llvm::Type::Int32Ty, SI->getNumSuccessors());
SI->addCase(ID, Dst);
}
}
// Set the destination code and branch.
Builder.CreateStore(ID, E->DestCode);
EmitBranch(E->FinallyBlock);
}
/// EmitObjCWeakRead - Code gen for loading value of a __weak
/// object: objc_read_weak (id *src)
///

114
clang/lib/CodeGen/CGStmt.cpp
View File

@ -133,12 +133,8 @@ RValue CodeGenFunction::EmitCompoundStmt(const CompoundStmt &S, bool GetLast,
// Keep track of the current cleanup stack depth.
size_t CleanupStackDepth = CleanupEntries.size();
bool OldDidCallStackSave = DidCallStackSave;
// Push a null stack save value.
StackSaveValues.push_back(0);
for (CompoundStmt::const_body_iterator I = S.body_begin(),
E = S.body_end()-GetLast; I != E; ++I)
EmitStmt(*I);
@ -168,14 +164,6 @@ RValue CodeGenFunction::EmitCompoundStmt(const CompoundStmt &S, bool GetLast,
RV = EmitAnyExpr(cast<Expr>(LastStmt), AggLoc);
}
if (llvm::Value *V = StackSaveValues.pop_back_val()) {
StackDepth = V;
V = Builder.CreateLoad(V, "tmp");
llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::stackrestore);
Builder.CreateCall(F, V);
}
DidCallStackSave = OldDidCallStackSave;
EmitCleanupBlocks(CleanupStackDepth);
@ -202,47 +190,6 @@ void CodeGenFunction::EmitBlock(llvm::BasicBlock *BB, bool IsFinished) {
Builder.SetInsertPoint(BB);
}
bool CodeGenFunction::EmitStackUpdate(llvm::Value *V) {
// If we're already at the depth we want...
if (StackDepth == V)
return false;
// V can be 0 here, if it is, be sure to start searching from the
// top of the function, as we want the next save after that point.
for (unsigned int i = 0; i < StackSaveValues.size(); ++i)
if (StackSaveValues[i] == V) {
// The actual depth is actually in the next used slot, if any.
while (++i < StackSaveValues.size()
&& (V = StackSaveValues[i]) == 0) ;
// If there were no other depth changes, we don't need any
// adjustments.
if (V) {
V = Builder.CreateLoad(V, "tmp");
// and restore it.
llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::stackrestore);
Builder.CreateCall(F, V);
}
} else return true;
return false;
}
bool CodeGenFunction::EmitStackUpdate(const void *S) {
if (StackDepthMap.find(S) == StackDepthMap.end()) {
// If we can't find it, just remember the depth now,
// so we can validate it later.
// FIXME: We need to save a place to insert the adjustment,
// if needed, here, sa that later in EmitLabel, we can
// backpatch the adjustment into that place, instead of
// saying unsupported.
StackDepthMap[S] = StackDepth;
return false;
}
// Find applicable stack depth, if any...
llvm::Value *V = StackDepthMap[S];
return EmitStackUpdate(V);
}
void CodeGenFunction::EmitBranch(llvm::BasicBlock *Target) {
// Emit a branch from the current block to the target one if this
// was a real block. If this was just a fall-through block after a
@ -260,31 +207,8 @@ void CodeGenFunction::EmitBranch(llvm::BasicBlock *Target) {
Builder.ClearInsertionPoint();
}
bool CodeGenFunction::StackFixupAtLabel(const void *S) {
if (StackDepthMap.find(S) == StackDepthMap.end()) {
// We need to remember the stack depth so that we can readjust the
// stack back to the right depth for this label if we want to
// transfer here from a different depth.
StackDepthMap[S] = StackDepth;
} else {
if (StackDepthMap[S] != StackDepth) {
// FIXME: Sema needs to ckeck for jumps that cross decls with
// initializations for C++, and all VLAs, not just the first in
// a block that does a stacksave.
// FIXME: We need to save a place to insert the adjustment
// when we do a EmitStackUpdate on a forward jump, and then
// backpatch the adjustment into that place.
return true;
}
}
return false;
}
void CodeGenFunction::EmitLabel(const LabelStmt &S) {
llvm::BasicBlock *NextBB = getBasicBlockForLabel(&S);
if (StackFixupAtLabel(&S))
CGM.ErrorUnsupported(&S, "forward goto inside scope with VLA");
EmitBlock(NextBB);
EmitBlock(getBasicBlockForLabel(&S));
}
@ -294,36 +218,16 @@ void CodeGenFunction::EmitLabelStmt(const LabelStmt &S) {
}
void CodeGenFunction::EmitGotoStmt(const GotoStmt &S) {
// FIXME: Implement goto out in @try or @catch blocks.
if (!ObjCEHStack.empty()) {
CGM.ErrorUnsupported(&S, "goto inside an Obj-C exception block");
return;
}
// If this code is reachable then emit a stop point (if generating
// debug info). We have to do this ourselves because we are on the
// "simple" statement path.
if (HaveInsertPoint())
EmitStopPoint(&S);
// We need to adjust the stack, if the destination was (will be) at
// a different depth.
if (EmitStackUpdate(S.getLabel()))
// FIXME: Move to semq and assert here, codegen isn't the right
// time to be checking.
CGM.ErrorUnsupported(S.getLabel(),
"invalid goto to VLA scope that has finished");
EmitBranchThroughCleanup(getBasicBlockForLabel(S.getLabel()));
}
void CodeGenFunction::EmitIndirectGotoStmt(const IndirectGotoStmt &S) {
// FIXME: Implement indirect goto in @try or @catch blocks.
if (!ObjCEHStack.empty()) {
CGM.ErrorUnsupported(&S, "goto inside an Obj-C exception block");
return;
}
// Emit initial switch which will be patched up later by
// EmitIndirectSwitches(). We need a default dest, so we use the
// current BB, but this is overwritten.
@ -557,13 +461,6 @@ void CodeGenFunction::EmitReturnOfRValue(RValue RV, QualType Ty) {
/// if the function returns void, or may be missing one if the function returns
/// non-void. Fun stuff :).
void CodeGenFunction::EmitReturnStmt(const ReturnStmt &S) {
for (unsigned i = 0; i < StackSaveValues.size(); i++) {
if (StackSaveValues[i]) {
CGM.ErrorUnsupported(&S, "return inside scope with VLA");
return;
}
}
// Emit the result value, even if unused, to evalute the side effects.
const Expr *RV = S.getRetValue();
@ -584,15 +481,6 @@ void CodeGenFunction::EmitReturnStmt(const ReturnStmt &S) {
EmitAggExpr(RV, ReturnValue, false);
}
if (!ObjCEHStack.empty()) {
for (ObjCEHStackType::reverse_iterator i = ObjCEHStack.rbegin(),
e = ObjCEHStack.rend(); i != e; ++i) {
llvm::BasicBlock *ReturnPad = createBasicBlock("return.pad");
EmitJumpThroughFinally(*i, ReturnPad);
EmitBlock(ReturnPad);
}
}
EmitBranchThroughCleanup(ReturnBlock);
}

2
clang/lib/CodeGen/CodeGenFunction.cpp
View File

@ -24,7 +24,7 @@ using namespace CodeGen;
CodeGenFunction::CodeGenFunction(CodeGenModule &cgm)
: CGM(cgm), Target(CGM.getContext().Target), SwitchInsn(NULL),
CaseRangeBlock(NULL), StackDepth(0) {
CaseRangeBlock(NULL) {
LLVMIntTy = ConvertType(getContext().IntTy);
LLVMPointerWidth = Target.getPointerWidth(0);
}

78
clang/lib/CodeGen/CodeGenFunction.h
View File

@ -88,47 +88,10 @@ public:
uint32_t LLVMPointerWidth;
public:
// FIXME: The following should be private once EH code is moved out of NeXT
// runtime.
// ObjCEHStack - This keeps track of which object to rethrow from inside
// @catch blocks and which @finally block exits from an EH scope should be
// chained through.
struct ObjCEHEntry {
ObjCEHEntry(llvm::BasicBlock *fb, llvm::SwitchInst *fs, llvm::Value *dc)
: FinallyBlock(fb), FinallySwitch(fs),
DestCode(dc) {}
/// Entry point to the finally block.
llvm::BasicBlock *FinallyBlock;
/// Switch instruction which runs at the end of the finally block to forward
/// jumps through the finally block.
llvm::SwitchInst *FinallySwitch;
/// Variable holding the code for the destination of a jump through the
/// @finally block.
llvm::Value *DestCode;
};
/// ObjCEHValueStack - Stack of exception objects being handled, during IR
/// generation for a @catch block.
/// ObjCEHValueStack - Stack of Objective-C exception values, used for
/// rethrows.
llvm::SmallVector<llvm::Value*, 8> ObjCEHValueStack;
typedef llvm::SmallVector<ObjCEHEntry*, 8> ObjCEHStackType;
ObjCEHStackType ObjCEHStack;
/// EmitJumpThroughFinally - Emit a branch from the current insert point
/// through the finally handling code for \arg Entry and then on to \arg
/// Dest. It is legal to call this function even if there is no current
/// insertion point.
///
/// \param ExecuteTryExit - When true, the try_exit runtime function should be
/// called prior to executing the finally code.
void EmitJumpThroughFinally(ObjCEHEntry *Entry, llvm::BasicBlock *Dest);
void EmitJumpThroughFinally(llvm::BasicBlock *Dest);
/// PushCleanupBlock - Push a new cleanup entry on the stack and set the
/// passed in block as the cleanup block.
void PushCleanupBlock(llvm::BasicBlock *CleanupBlock);
@ -229,47 +192,10 @@ private:
// enter/leave scopes.
llvm::DenseMap<const VariableArrayType*, llvm::Value*> VLASizeMap;
/// StackDepth - This keeps track of the stack depth. It is used to notice
/// when control flow results in a change in stack depth and to arrange for
/// the appropriate stack depth to be restored. VLAs are the primary means by
/// which the stack depth changes.
llvm::Value *StackDepth;
/// DidCallStackSave - Whether llvm.stacksave has been called. Used to avoid
/// calling llvm.stacksave for multiple VLAs in the same scope.
bool DidCallStackSave;
/// StackSaveValues - A stack(!) of stack save values. When a new scope is
/// entered, a null is pushed on this stack. If a VLA is emitted, then the
/// return value of llvm.stacksave() is stored at the top of this stack.
llvm::SmallVector<llvm::Value*, 8> StackSaveValues;
/// StackDepthMap - A association of stack depth that will be in effect for
/// each label. If control flow is transferred to a label, we have to restore
/// the desired stack depth at the destination label, beore we transfer to
/// that label.
llvm::DenseMap<const void*, llvm::Value *> StackDepthMap;
/// StackFixupAtLabel - Routine to adjust the stack to the depth the stack
/// should be at by the time we transfer control flow to the label. This is
/// called as we emit destinations for control flow, such as user labels for
/// goto statements and compiler generated labels for break and continue
/// processsing. We return true, if for any reason we can't generate code for
/// the construct yet. See EmitStackUpdate for the paired routine to mark the
/// branch.
bool StackFixupAtLabel(const void *);
/// EmitStackUpdate - Routine to adjust the stack to the depth the stack
/// should be at by the time we transfer control flow to the label. This is
/// called just before emitting branches for user level goto processing,
/// branhes for break or continue processing. The llvm::value overload is
/// used when handling break and continue, as we know the stack depth
/// directly. We return true, if for any reason we can't generate code for
/// the construct yet. See StackFixupAtLabel for the paired routine to mark
/// the destinations.
bool EmitStackUpdate(llvm::Value *V);
bool EmitStackUpdate(const void *S);
struct CleanupEntry {
/// CleanupBlock - The block of code that does the actual cleanup.
llvm::BasicBlock *CleanupBlock;