llvm-6502/include/llvm/IR/CallSite.h
Nick Lewycky 05da4dd998 Improve 'tail' call marking in TRE. A bootstrap of clang goes from 375k calls marked tail in the IR to 470k, however this improvement does not carry into an improvement of the call/jmp ratio on x86. The most common pattern is a tail call + br to a block with nothing but a 'ret'.
The number of tail call to loop conversions remains the same (1618 by my count).

The new algorithm does a local scan over the use-def chains to identify local "alloca-derived" values, as well as points where the alloca could escape. Then, a visit over the CFG marks blocks as being before or after the allocas have escaped, and annotates the calls accordingly.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208017 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-05 23:59:03 +00:00

367 lines
12 KiB
C++

//===- CallSite.h - Abstract Call & Invoke instrs ---------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the CallSite class, which is a handy wrapper for code that
// wants to treat Call and Invoke instructions in a generic way. When in non-
// mutation context (e.g. an analysis) ImmutableCallSite should be used.
// Finally, when some degree of customization is necessary between these two
// extremes, CallSiteBase<> can be supplied with fine-tuned parameters.
//
// NOTE: These classes are supposed to have "value semantics". So they should be
// passed by value, not by reference; they should not be "new"ed or "delete"d.
// They are efficiently copyable, assignable and constructable, with cost
// equivalent to copying a pointer (notice that they have only a single data
// member). The internal representation carries a flag which indicates which of
// the two variants is enclosed. This allows for cheaper checks when various
// accessors of CallSite are employed.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_IR_CALLSITE_H
#define LLVM_IR_CALLSITE_H
#include "llvm/ADT/PointerIntPair.h"
#include "llvm/IR/Attributes.h"
#include "llvm/IR/CallingConv.h"
#include "llvm/IR/Instructions.h"
namespace llvm {
class CallInst;
class InvokeInst;
template <typename FunTy = const Function,
typename ValTy = const Value,
typename UserTy = const User,
typename InstrTy = const Instruction,
typename CallTy = const CallInst,
typename InvokeTy = const InvokeInst,
typename IterTy = User::const_op_iterator>
class CallSiteBase {
protected:
PointerIntPair<InstrTy*, 1, bool> I;
public:
CallSiteBase() : I(nullptr, false) {}
CallSiteBase(CallTy *CI) : I(CI, true) { assert(CI); }
CallSiteBase(InvokeTy *II) : I(II, false) { assert(II); }
CallSiteBase(ValTy *II) { *this = get(II); }
protected:
/// CallSiteBase::get - This static method is sort of like a constructor. It
/// will create an appropriate call site for a Call or Invoke instruction, but
/// it can also create a null initialized CallSiteBase object for something
/// which is NOT a call site.
///
static CallSiteBase get(ValTy *V) {
if (InstrTy *II = dyn_cast<InstrTy>(V)) {
if (II->getOpcode() == Instruction::Call)
return CallSiteBase(static_cast<CallTy*>(II));
else if (II->getOpcode() == Instruction::Invoke)
return CallSiteBase(static_cast<InvokeTy*>(II));
}
return CallSiteBase();
}
public:
/// isCall - true if a CallInst is enclosed.
/// Note that !isCall() does not mean it is an InvokeInst enclosed,
/// it also could signify a NULL Instruction pointer.
bool isCall() const { return I.getInt(); }
/// isInvoke - true if a InvokeInst is enclosed.
///
bool isInvoke() const { return getInstruction() && !I.getInt(); }
InstrTy *getInstruction() const { return I.getPointer(); }
InstrTy *operator->() const { return I.getPointer(); }
LLVM_EXPLICIT operator bool() const { return I.getPointer(); }
/// getCalledValue - Return the pointer to function that is being called.
///
ValTy *getCalledValue() const {
assert(getInstruction() && "Not a call or invoke instruction!");
return *getCallee();
}
/// getCalledFunction - Return the function being called if this is a direct
/// call, otherwise return null (if it's an indirect call).
///
FunTy *getCalledFunction() const {
return dyn_cast<FunTy>(getCalledValue());
}
/// setCalledFunction - Set the callee to the specified value.
///
void setCalledFunction(Value *V) {
assert(getInstruction() && "Not a call or invoke instruction!");
*getCallee() = V;
}
/// isCallee - Determine whether the passed iterator points to the
/// callee operand's Use.
bool isCallee(Value::const_user_iterator UI) const {
return isCallee(&UI.getUse());
}
/// Determine whether this Use is the callee operand's Use.
bool isCallee(const Use *U) const { return getCallee() == U; }
ValTy *getArgument(unsigned ArgNo) const {
assert(arg_begin() + ArgNo < arg_end() && "Argument # out of range!");
return *(arg_begin() + ArgNo);
}
void setArgument(unsigned ArgNo, Value* newVal) {
assert(getInstruction() && "Not a call or invoke instruction!");
assert(arg_begin() + ArgNo < arg_end() && "Argument # out of range!");
getInstruction()->setOperand(ArgNo, newVal);
}
/// Given a value use iterator, returns the argument that corresponds to it.
/// Iterator must actually correspond to an argument.
unsigned getArgumentNo(Value::const_user_iterator I) const {
return getArgumentNo(&I.getUse());
}
/// Given a use for an argument, get the argument number that corresponds to
/// it.
unsigned getArgumentNo(const Use *U) const {
assert(getInstruction() && "Not a call or invoke instruction!");
assert(arg_begin() <= U && U < arg_end()
&& "Argument # out of range!");
return U - arg_begin();
}
/// arg_iterator - The type of iterator to use when looping over actual
/// arguments at this call site.
typedef IterTy arg_iterator;
/// arg_begin/arg_end - Return iterators corresponding to the actual argument
/// list for a call site.
IterTy arg_begin() const {
assert(getInstruction() && "Not a call or invoke instruction!");
// Skip non-arguments
return (*this)->op_begin();
}
IterTy arg_end() const { return (*this)->op_end() - getArgumentEndOffset(); }
bool arg_empty() const { return arg_end() == arg_begin(); }
unsigned arg_size() const { return unsigned(arg_end() - arg_begin()); }
/// getType - Return the type of the instruction that generated this call site
///
Type *getType() const { return (*this)->getType(); }
/// getCaller - Return the caller function for this call site
///
FunTy *getCaller() const { return (*this)->getParent()->getParent(); }
/// \brief Tests if this call site must be tail call optimized. Only a
/// CallInst can be tail call optimized.
bool isMustTailCall() const {
return isCall() && cast<CallInst>(getInstruction())->isMustTailCall();
}
/// \brief Tests if this call site is marked as a tail call.
bool isTailCall() const {
return isCall() && cast<CallInst>(getInstruction())->isTailCall();
}
#define CALLSITE_DELEGATE_GETTER(METHOD) \
InstrTy *II = getInstruction(); \
return isCall() \
? cast<CallInst>(II)->METHOD \
: cast<InvokeInst>(II)->METHOD
#define CALLSITE_DELEGATE_SETTER(METHOD) \
InstrTy *II = getInstruction(); \
if (isCall()) \
cast<CallInst>(II)->METHOD; \
else \
cast<InvokeInst>(II)->METHOD
/// getCallingConv/setCallingConv - get or set the calling convention of the
/// call.
CallingConv::ID getCallingConv() const {
CALLSITE_DELEGATE_GETTER(getCallingConv());
}
void setCallingConv(CallingConv::ID CC) {
CALLSITE_DELEGATE_SETTER(setCallingConv(CC));
}
/// getAttributes/setAttributes - get or set the parameter attributes of
/// the call.
const AttributeSet &getAttributes() const {
CALLSITE_DELEGATE_GETTER(getAttributes());
}
void setAttributes(const AttributeSet &PAL) {
CALLSITE_DELEGATE_SETTER(setAttributes(PAL));
}
/// \brief Return true if this function has the given attribute.
bool hasFnAttr(Attribute::AttrKind A) const {
CALLSITE_DELEGATE_GETTER(hasFnAttr(A));
}
/// \brief Return true if the call or the callee has the given attribute.
bool paramHasAttr(unsigned i, Attribute::AttrKind A) const {
CALLSITE_DELEGATE_GETTER(paramHasAttr(i, A));
}
/// @brief Extract the alignment for a call or parameter (0=unknown).
uint16_t getParamAlignment(uint16_t i) const {
CALLSITE_DELEGATE_GETTER(getParamAlignment(i));
}
/// \brief Return true if the call should not be treated as a call to a
/// builtin.
bool isNoBuiltin() const {
CALLSITE_DELEGATE_GETTER(isNoBuiltin());
}
/// @brief Return true if the call should not be inlined.
bool isNoInline() const {
CALLSITE_DELEGATE_GETTER(isNoInline());
}
void setIsNoInline(bool Value = true) {
CALLSITE_DELEGATE_SETTER(setIsNoInline(Value));
}
/// @brief Determine if the call does not access memory.
bool doesNotAccessMemory() const {
CALLSITE_DELEGATE_GETTER(doesNotAccessMemory());
}
void setDoesNotAccessMemory() {
CALLSITE_DELEGATE_SETTER(setDoesNotAccessMemory());
}
/// @brief Determine if the call does not access or only reads memory.
bool onlyReadsMemory() const {
CALLSITE_DELEGATE_GETTER(onlyReadsMemory());
}
void setOnlyReadsMemory() {
CALLSITE_DELEGATE_SETTER(setOnlyReadsMemory());
}
/// @brief Determine if the call cannot return.
bool doesNotReturn() const {
CALLSITE_DELEGATE_GETTER(doesNotReturn());
}
void setDoesNotReturn() {
CALLSITE_DELEGATE_SETTER(setDoesNotReturn());
}
/// @brief Determine if the call cannot unwind.
bool doesNotThrow() const {
CALLSITE_DELEGATE_GETTER(doesNotThrow());
}
void setDoesNotThrow() {
CALLSITE_DELEGATE_SETTER(setDoesNotThrow());
}
#undef CALLSITE_DELEGATE_GETTER
#undef CALLSITE_DELEGATE_SETTER
/// @brief Determine whether this argument is not captured.
bool doesNotCapture(unsigned ArgNo) const {
return paramHasAttr(ArgNo + 1, Attribute::NoCapture);
}
/// @brief Determine whether this argument is passed by value.
bool isByValArgument(unsigned ArgNo) const {
return paramHasAttr(ArgNo + 1, Attribute::ByVal);
}
/// @brief Determine whether this argument is passed in an alloca.
bool isInAllocaArgument(unsigned ArgNo) const {
return paramHasAttr(ArgNo + 1, Attribute::InAlloca);
}
/// @brief Determine whether this argument is passed by value or in an alloca.
bool isByValOrInAllocaArgument(unsigned ArgNo) const {
return paramHasAttr(ArgNo + 1, Attribute::ByVal) ||
paramHasAttr(ArgNo + 1, Attribute::InAlloca);
}
/// @brief Determine if there are is an inalloca argument. Only the last
/// argument can have the inalloca attribute.
bool hasInAllocaArgument() const {
return paramHasAttr(arg_size(), Attribute::InAlloca);
}
bool doesNotAccessMemory(unsigned ArgNo) const {
return paramHasAttr(ArgNo + 1, Attribute::ReadNone);
}
bool onlyReadsMemory(unsigned ArgNo) const {
return paramHasAttr(ArgNo + 1, Attribute::ReadOnly) ||
paramHasAttr(ArgNo + 1, Attribute::ReadNone);
}
/// hasArgument - Returns true if this CallSite passes the given Value* as an
/// argument to the called function.
bool hasArgument(const Value *Arg) const {
for (arg_iterator AI = this->arg_begin(), E = this->arg_end(); AI != E;
++AI)
if (AI->get() == Arg)
return true;
return false;
}
private:
unsigned getArgumentEndOffset() const {
if (isCall())
return 1; // Skip Callee
else
return 3; // Skip BB, BB, Callee
}
IterTy getCallee() const {
if (isCall()) // Skip Callee
return cast<CallInst>(getInstruction())->op_end() - 1;
else // Skip BB, BB, Callee
return cast<InvokeInst>(getInstruction())->op_end() - 3;
}
};
class CallSite : public CallSiteBase<Function, Value, User, Instruction,
CallInst, InvokeInst, User::op_iterator> {
typedef CallSiteBase<Function, Value, User, Instruction,
CallInst, InvokeInst, User::op_iterator> Base;
public:
CallSite() {}
CallSite(Base B) : Base(B) {}
CallSite(Value* V) : Base(V) {}
CallSite(CallInst *CI) : Base(CI) {}
CallSite(InvokeInst *II) : Base(II) {}
CallSite(Instruction *II) : Base(II) {}
bool operator==(const CallSite &CS) const { return I == CS.I; }
bool operator!=(const CallSite &CS) const { return I != CS.I; }
bool operator<(const CallSite &CS) const {
return getInstruction() < CS.getInstruction();
}
private:
User::op_iterator getCallee() const;
};
/// ImmutableCallSite - establish a view to a call site for examination
class ImmutableCallSite : public CallSiteBase<> {
typedef CallSiteBase<> Base;
public:
ImmutableCallSite(const Value* V) : Base(V) {}
ImmutableCallSite(const CallInst *CI) : Base(CI) {}
ImmutableCallSite(const InvokeInst *II) : Base(II) {}
ImmutableCallSite(const Instruction *II) : Base(II) {}
ImmutableCallSite(CallSite CS) : Base(CS.getInstruction()) {}
};
} // End llvm namespace
#endif