ldc/gen/dvalue.cpp
Martin 963a10b225 Let DValue types handle memory-only types consistently
I.e., disallow memory-only values from being represented as DImValues
and disallow getRVal() for such types instead of returning the address.
2016-06-13 22:30:14 +02:00

131 lines
3.7 KiB
C++
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

//===-- dvalue.cpp --------------------------------------------------------===//
//
// LDC the LLVM D compiler
//
// This file is distributed under the BSD-style LDC license. See the LICENSE
// file for details.
//
//===----------------------------------------------------------------------===//
#include "gen/dvalue.h"
#include "declaration.h"
#include "gen/irstate.h"
#include "gen/llvm.h"
#include "gen/llvmhelpers.h"
#include "gen/logger.h"
#include "gen/tollvm.h"
namespace {
bool isDefinedInFuncEntryBB(LLValue *v) {
auto instr = llvm::dyn_cast<llvm::Instruction>(v);
if (!instr) {
// Global, constant, ...
return true;
}
auto bb = instr->getParent();
if (bb != &(bb->getParent()->getEntryBlock())) {
return false;
}
// An invoke instruction in the entry BB does not necessarily dominate the
// rest of the function because of the failure path.
return !llvm::isa<llvm::InvokeInst>(instr);
}
}
////////////////////////////////////////////////////////////////////////////////
bool DValue::definedInFuncEntryBB() { return isDefinedInFuncEntryBB(val); }
////////////////////////////////////////////////////////////////////////////////
DImValue::DImValue(Type *t, llvm::Value *v) : DValue(t, v) {
assert(!DtoIsInMemoryOnly(t) &&
"Cannot represent memory-only type as immediate DValue");
}
////////////////////////////////////////////////////////////////////////////////
DConstValue::DConstValue(Type *t, llvm::Constant *con) : DValue(t, con) {}
////////////////////////////////////////////////////////////////////////////////
static bool checkVarValueType(LLType *t, bool extraDeref) {
if (extraDeref) {
llvm::PointerType *pt = llvm::dyn_cast<llvm::PointerType>(t);
if (!pt) {
return false;
}
t = pt->getElementType();
}
llvm::PointerType *pt = llvm::dyn_cast<llvm::PointerType>(t);
if (!pt) {
return false;
}
// bools should not be stored as i1 any longer.
if (pt->getElementType() == llvm::Type::getInt1Ty(gIR->context())) {
return false;
}
return true;
}
DVarValue::DVarValue(Type *t, LLValue *v, bool isSpecialRefVar)
: DValue(t, v), isSpecialRefVar(isSpecialRefVar) {
assert(v && "Unexpected null llvm::Value.");
assert(checkVarValueType(v->getType(), isSpecialRefVar));
}
LLValue *DVarValue::getLVal() { return isSpecialRefVar ? DtoLoad(val) : val; }
LLValue *DVarValue::getRVal() {
LLValue *storage = val;
if (isSpecialRefVar)
storage = DtoLoad(storage);
if (DtoIsInMemoryOnly(type->toBasetype())) {
llvm_unreachable("getRVal() for memory-only type");
return nullptr;
}
LLValue *rawValue = DtoLoad(storage);
if (type->toBasetype()->ty == Tbool) {
assert(rawValue->getType() == llvm::Type::getInt8Ty(gIR->context()));
return gIR->ir->CreateTrunc(rawValue,
llvm::Type::getInt1Ty(gIR->context()));
}
return rawValue;
}
LLValue *DVarValue::getRefStorage() {
assert(isSpecialRefVar);
return val;
}
////////////////////////////////////////////////////////////////////////////////
DSliceValue::DSliceValue(Type *t, LLValue *length, LLValue *ptr)
: DValue(t, DtoAggrPair(length, ptr)) {}
LLValue *DSliceValue::getLength() { return DtoExtractValue(val, 0, ".len"); }
LLValue *DSliceValue::getPtr() { return DtoExtractValue(val, 1, ".ptr"); }
////////////////////////////////////////////////////////////////////////////////
DFuncValue::DFuncValue(Type *t, FuncDeclaration *fd, LLValue *v, LLValue *vt)
: DValue(t, v), func(fd), vthis(vt) {}
DFuncValue::DFuncValue(FuncDeclaration *fd, LLValue *v, LLValue *vt)
: DValue(fd->type, v), func(fd), vthis(vt) {}
bool DFuncValue::definedInFuncEntryBB() {
return isDefinedInFuncEntryBB(val) &&
(!vthis || isDefinedInFuncEntryBB(vthis));
}