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

Generalize statepoint lowering to use ImmutableStatepoint. Move statepoint lowering into a separate function 'LowerStatepoint' which uses ImmutableStatepoint instead of a CallInst. Also related utility functions are changed to receive ImmutableCallSite. 

Differential Revision: http://reviews.llvm.org/D7756 

llvm-svn: 230017
This commit is contained in:
Igor Laevsky 2015-02-20 15:28:35 +00:00
parent 7af984b710
commit 7fc58a4ad8
3 changed files with 42 additions and 40 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
llvm/include/llvm/IR/Statepoint.h
View File

@ -17,6 +17,7 @@
#define __LLVM_IR_STATEPOINT_H
#include "llvm/ADT/iterator_range.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/CallSite.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Intrinsics.h"

3
llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.h
View File

@ -20,6 +20,7 @@
#include "llvm/CodeGen/SelectionDAG.h"
#include "llvm/CodeGen/SelectionDAGNodes.h"
#include "llvm/IR/CallSite.h"
#include "llvm/IR/Statepoint.h"
#include "llvm/IR/Constants.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Target/TargetLowering.h"
@ -660,6 +661,8 @@ public:
/// references that need to refer to the last resulting block.
void UpdateSplitBlock(MachineBasicBlock *First, MachineBasicBlock *Last);
// This function is responsible for the whole statepoint lowering process.
void LowerStatepoint(ImmutableStatepoint Statepoint);
private:
std::pair<SDValue, SDValue> lowerInvokable(
TargetLowering::CallLoweringInfo &CLI,

78
llvm/lib/CodeGen/SelectionDAG/StatepointLowering.cpp
View File

@ -223,32 +223,28 @@ static void removeDuplicatesGCPtrs(SmallVectorImpl<const Value *> &Bases,
/// Extract call from statepoint, lower it and return pointer to the
/// call node. Also update NodeMap so that getValue(statepoint) will
/// reference lowered call result
static SDNode *lowerCallFromStatepoint(const CallInst &CI,
static SDNode *lowerCallFromStatepoint(ImmutableStatepoint StatepointSite,
SelectionDAGBuilder &Builder) {
assert(Intrinsic::experimental_gc_statepoint ==
dyn_cast<IntrinsicInst>(&CI)->getIntrinsicID() &&
"function called must be the statepoint function");
ImmutableStatepoint StatepointOperands(&CI);
ImmutableCallSite CS(StatepointSite.getCallSite());
// Lower the actual call itself - This is a bit of a hack, but we want to
// avoid modifying the actual lowering code. This is similiar in intent to
// the LowerCallOperands mechanism used by PATCHPOINT, but is structured
// differently. Hopefully, this is slightly more robust w.r.t. calling
// convention, return values, and other function attributes.
Value *ActualCallee = const_cast<Value *>(StatepointOperands.actualCallee());
Value *ActualCallee = const_cast<Value *>(StatepointSite.actualCallee());
std::vector<Value *> Args;
CallInst::const_op_iterator arg_begin = StatepointOperands.call_args_begin();
CallInst::const_op_iterator arg_end = StatepointOperands.call_args_end();
CallInst::const_op_iterator arg_begin = StatepointSite.call_args_begin();
CallInst::const_op_iterator arg_end = StatepointSite.call_args_end();
Args.insert(Args.end(), arg_begin, arg_end);
// TODO: remove the creation of a new instruction! We should not be
// modifying the IR (even temporarily) at this point.
CallInst *Tmp = CallInst::Create(ActualCallee, Args);
Tmp->setTailCall(CI.isTailCall());
Tmp->setCallingConv(CI.getCallingConv());
Tmp->setAttributes(CI.getAttributes());
Tmp->setTailCall(CS.isTailCall());
Tmp->setCallingConv(CS.getCallingConv());
Tmp->setAttributes(CS.getAttributes());
Builder.LowerCallTo(Tmp, Builder.getValue(ActualCallee), false);
// Handle the return value of the call iff any.
@ -257,10 +253,10 @@ static SDNode *lowerCallFromStatepoint(const CallInst &CI,
// The value of the statepoint itself will be the value of call itself.
// We'll replace the actually call node shortly. gc_result will grab
// this value.
Builder.setValue(&CI, Builder.getValue(Tmp));
Builder.setValue(CS.getInstruction(), Builder.getValue(Tmp));
} else {
// The token value is never used from here on, just generate a poison value
Builder.setValue(&CI, Builder.DAG.getIntPtrConstant(-1));
Builder.setValue(CS.getInstruction(), Builder.DAG.getIntPtrConstant(-1));
}
// Remove the fake entry we created so we don't have a hanging reference
// after we delete this node.
@ -305,18 +301,11 @@ static void
getIncomingStatepointGCValues(SmallVectorImpl<const Value *> &Bases,
SmallVectorImpl<const Value *> &Ptrs,
SmallVectorImpl<const Value *> &Relocs,
ImmutableCallSite Statepoint,
ImmutableStatepoint StatepointSite,
SelectionDAGBuilder &Builder) {
// Search for relocated pointers. Note that working backwards from the
// gc_relocates ensures that we only get pairs which are actually relocated
// and used after the statepoint.
// TODO: This logic should probably become a utility function in Statepoint.h
for (const User *U : cast<CallInst>(Statepoint.getInstruction())->users()) {
if (!isGCRelocate(U)) {
continue;
}
GCRelocateOperands relocateOpers(U);
Relocs.push_back(cast<Value>(U));
for (GCRelocateOperands relocateOpers :
StatepointSite.getRelocates(StatepointSite)) {
Relocs.push_back(relocateOpers.getUnderlyingCallSite().getInstruction());
Bases.push_back(relocateOpers.basePtr());
Ptrs.push_back(relocateOpers.derivedPtr());
}
@ -409,7 +398,7 @@ static void lowerIncomingStatepointValue(SDValue Incoming,
/// statepoint. The chain nodes will have already been created and the DAG root
/// will be set to the last value spilled (if any were).
static void lowerStatepointMetaArgs(SmallVectorImpl<SDValue> &Ops,
ImmutableStatepoint Statepoint,
ImmutableStatepoint StatepointSite,
SelectionDAGBuilder &Builder) {
// Lower the deopt and gc arguments for this statepoint. Layout will
@ -417,7 +406,7 @@ static void lowerStatepointMetaArgs(SmallVectorImpl<SDValue> &Ops,
SmallVector<const Value *, 64> Bases, Ptrs, Relocations;
getIncomingStatepointGCValues(Bases, Ptrs, Relocations,
Statepoint.getCallSite(), Builder);
StatepointSite, Builder);
#ifndef NDEBUG
// Check that each of the gc pointer and bases we've gotten out of the
@ -457,7 +446,8 @@ static void lowerStatepointMetaArgs(SmallVectorImpl<SDValue> &Ops,
// particular value. This is purely an optimization over the code below and
// doesn't change semantics at all. It is important for performance that we
// reserve slots for both deopt and gc values before lowering either.
for (auto I = Statepoint.vm_state_begin() + 1, E = Statepoint.vm_state_end();
for (auto I = StatepointSite.vm_state_begin() + 1,
E = StatepointSite.vm_state_end();
I != E; ++I) {
Value *V = *I;
SDValue Incoming = Builder.getValue(V);
@ -473,13 +463,13 @@ static void lowerStatepointMetaArgs(SmallVectorImpl<SDValue> &Ops,
// First, prefix the list with the number of unique values to be
// lowered. Note that this is the number of *Values* not the
// number of SDValues required to lower them.
const int NumVMSArgs = Statepoint.numTotalVMSArgs();
const int NumVMSArgs = StatepointSite.numTotalVMSArgs();
Ops.push_back(
Builder.DAG.getTargetConstant(StackMaps::ConstantOp, MVT::i64));
Ops.push_back(Builder.DAG.getTargetConstant(NumVMSArgs, MVT::i64));
assert(NumVMSArgs + 1 == std::distance(Statepoint.vm_state_begin(),
Statepoint.vm_state_end()));
assert(NumVMSArgs + 1 == std::distance(StatepointSite.vm_state_begin(),
StatepointSite.vm_state_end()));
// The vm state arguments are lowered in an opaque manner. We do
// not know what type of values are contained within. We skip the
@ -487,7 +477,8 @@ static void lowerStatepointMetaArgs(SmallVectorImpl<SDValue> &Ops,
// explicitly just above. We could have left it in the loop and
// not done it explicitly, but it's far easier to understand this
// way.
for (auto I = Statepoint.vm_state_begin() + 1, E = Statepoint.vm_state_end();
for (auto I = StatepointSite.vm_state_begin() + 1,
E = StatepointSite.vm_state_end();
I != E; ++I) {
const Value *V = *I;
SDValue Incoming = Builder.getValue(V);
@ -506,28 +497,35 @@ static void lowerStatepointMetaArgs(SmallVectorImpl<SDValue> &Ops,
lowerIncomingStatepointValue(Incoming, Ops, Builder);
}
}
void SelectionDAGBuilder::visitStatepoint(const CallInst &CI) {
// Check some preconditions for sanity
assert(isStatepoint(&CI) &&
"function called must be the statepoint function");
LowerStatepoint(ImmutableStatepoint(&CI));
}
void SelectionDAGBuilder::LowerStatepoint(ImmutableStatepoint ISP) {
// The basic scheme here is that information about both the original call and
// the safepoint is encoded in the CallInst. We create a temporary call and
// lower it, then reverse engineer the calling sequence.
// Check some preconditions for sanity
assert(isStatepoint(&CI) &&
"function called must be the statepoint function");
NumOfStatepoints++;
// Clear state
StatepointLowering.startNewStatepoint(*this);
ImmutableCallSite CS(ISP.getCallSite());
#ifndef NDEBUG
// Consistency check
for (const User *U : CI.users()) {
for (const User *U : CS->users()) {
const CallInst *Call = cast<CallInst>(U);
if (isGCRelocate(Call))
StatepointLowering.scheduleRelocCall(*Call);
}
#endif
ImmutableStatepoint ISP(&CI);
#ifndef NDEBUG
// If this is a malformed statepoint, report it early to simplify debugging.
// This should catch any IR level mistake that's made when constructing or
@ -550,7 +548,7 @@ void SelectionDAGBuilder::visitStatepoint(const CallInst &CI) {
lowerStatepointMetaArgs(LoweredArgs, ISP, *this);
// Get call node, we will replace it later with statepoint
SDNode *CallNode = lowerCallFromStatepoint(CI, *this);
SDNode *CallNode = lowerCallFromStatepoint(ISP, *this);
// Construct the actual STATEPOINT node with all the appropriate arguments
// and return values.
@ -587,8 +585,8 @@ void SelectionDAGBuilder::visitStatepoint(const CallInst &CI) {
// Add a leading constant argument with the Flags and the calling convention
// masked together
CallingConv::ID CallConv = CI.getCallingConv();
int Flags = dyn_cast<ConstantInt>(CI.getArgOperand(2))->getZExtValue();
CallingConv::ID CallConv = CS.getCallingConv();
int Flags = dyn_cast<ConstantInt>(CS.getArgument(2))->getZExtValue();
assert(Flags == 0 && "not expected to be used");
Ops.push_back(DAG.getTargetConstant(StackMaps::ConstantOp, MVT::i64));
Ops.push_back(