[cfe-commits] r77738 - /cfe/trunk/lib/CodeGen/CGExprConstant.cpp
Anders Carlsson
andersca at mac.com
Fri Jul 31 14:48:56 PDT 2009
Author: andersca
Date: Fri Jul 31 16:48:56 2009
New Revision: 77738
URL: http://llvm.org/viewvc/llvm-project?rev=77738&view=rev
Log:
Remove the old struct builder code.
Modified:
cfe/trunk/lib/CodeGen/CGExprConstant.cpp
Modified: cfe/trunk/lib/CodeGen/CGExprConstant.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGExprConstant.cpp?rev=77738&r1=77737&r2=77738&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGExprConstant.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGExprConstant.cpp Fri Jul 31 16:48:56 2009
@@ -467,188 +467,12 @@
return llvm::ConstantArray::get(AType, Elts);
}
- void InsertBitfieldIntoStruct(std::vector<llvm::Constant*>& Elts,
- FieldDecl* Field, Expr* E) {
- // Calculate the value to insert
- llvm::Constant *C = CGM.EmitConstantExpr(E, Field->getType(), CGF);
- if (!C)
- return;
-
- llvm::ConstantInt *CI = dyn_cast<llvm::ConstantInt>(C);
- if (!CI) {
- CGM.ErrorUnsupported(E, "bitfield initialization");
- return;
- }
- llvm::APInt V = CI->getValue();
-
- // Calculate information about the relevant field
- const llvm::Type* Ty = CI->getType();
- const llvm::TargetData &TD = CGM.getTypes().getTargetData();
- unsigned size = TD.getTypeAllocSizeInBits(Ty);
- CodeGenTypes::BitFieldInfo Info = CGM.getTypes().getBitFieldInfo(Field);
- unsigned FieldOffset = Info.FieldNo * size;
-
- FieldOffset += Info.Start;
-
- // Find where to start the insertion
- // FIXME: This is O(n^2) in the number of bit-fields!
- // FIXME: This won't work if the struct isn't completely packed!
- unsigned offset = 0, i = 0;
- while (offset < (FieldOffset & -8))
- offset += TD.getTypeAllocSizeInBits(Elts[i++]->getType());
-
- // Advance over 0 sized elements (must terminate in bounds since
- // the bitfield must have a size).
- while (TD.getTypeAllocSizeInBits(Elts[i]->getType()) == 0)
- ++i;
-
- // Promote the size of V if necessary
- // FIXME: This should never occur, but currently it can because initializer
- // constants are cast to bool, and because clang is not enforcing bitfield
- // width limits.
- if (Info.Size > V.getBitWidth())
- V.zext(Info.Size);
-
- // Insert the bits into the struct
- // FIXME: This algorthm is only correct on X86!
- // FIXME: THis algorthm assumes bit-fields only have byte-size elements!
- unsigned bitsToInsert = Info.Size;
- unsigned curBits = std::min(8 - (FieldOffset & 7), bitsToInsert);
- unsigned byte = V.getLoBits(curBits).getZExtValue() << (FieldOffset & 7);
- do {
- llvm::Constant* byteC =
- llvm::ConstantInt::get(llvm::Type::Int8Ty, byte);
- Elts[i] = llvm::ConstantExpr::getOr(Elts[i], byteC);
- ++i;
- V = V.lshr(curBits);
- bitsToInsert -= curBits;
-
- if (!bitsToInsert)
- break;
-
- curBits = bitsToInsert > 8 ? 8 : bitsToInsert;
- byte = V.getLoBits(curBits).getZExtValue();
- } while (true);
- }
-
llvm::Constant *EmitStructInitialization(InitListExpr *ILE) {
return ConstStructBuilder::BuildStruct(CGM, CGF, ILE);
-
- // FIXME: Remove the old struct builder once we're sure that the new one
- // works well enough!
- const llvm::StructType *SType =
- cast<llvm::StructType>(ConvertType(ILE->getType()));
- RecordDecl *RD = ILE->getType()->getAs<RecordType>()->getDecl();
- std::vector<llvm::Constant*> Elts;
-
- // Initialize the whole structure to zero.
- // FIXME: This doesn't handle member pointers correctly!
- for (unsigned i = 0; i < SType->getNumElements(); ++i) {
- const llvm::Type *FieldTy = SType->getElementType(i);
- Elts.push_back(llvm::Constant::getNullValue(FieldTy));
- }
-
- // Copy initializer elements. Skip padding fields.
- unsigned EltNo = 0; // Element no in ILE
- bool RewriteType = false;
- for (RecordDecl::field_iterator Field = RD->field_begin(),
- FieldEnd = RD->field_end();
- EltNo < ILE->getNumInits() && Field != FieldEnd; ++Field) {
- if (Field->isBitField()) {
- if (!Field->getIdentifier())
- continue;
- InsertBitfieldIntoStruct(Elts, *Field, ILE->getInit(EltNo));
- } else {
- unsigned FieldNo = CGM.getTypes().getLLVMFieldNo(*Field);
- llvm::Constant *C = CGM.EmitConstantExpr(ILE->getInit(EltNo),
- Field->getType(), CGF);
- if (!C) return 0;
- RewriteType |= (C->getType() != Elts[FieldNo]->getType());
- Elts[FieldNo] = C;
- }
- EltNo++;
- }
-
- if (RewriteType) {
- // FIXME: Make this work for non-packed structs
- assert(SType->isPacked() && "Cannot recreate unpacked structs");
- std::vector<const llvm::Type*> Types;
- for (unsigned i = 0; i < Elts.size(); ++i)
- Types.push_back(Elts[i]->getType());
- SType = llvm::StructType::get(Types, true);
- }
-
- return llvm::ConstantStruct::get(SType, Elts);
}
-
- llvm::Constant *EmitUnion(llvm::Constant *C, const llvm::Type *Ty) {
- if (!C)
- return 0;
-
- // Build a struct with the union sub-element as the first member,
- // and padded to the appropriate size
- std::vector<llvm::Constant*> Elts;
- std::vector<const llvm::Type*> Types;
- Elts.push_back(C);
- Types.push_back(C->getType());
- unsigned CurSize = CGM.getTargetData().getTypeAllocSize(C->getType());
- unsigned TotalSize = CGM.getTargetData().getTypeAllocSize(Ty);
-
- assert(CurSize <= TotalSize && "Union size mismatch!");
- if (unsigned NumPadBytes = TotalSize - CurSize) {
- const llvm::Type *Ty = llvm::Type::Int8Ty;
- if (NumPadBytes > 1)
- Ty = llvm::ArrayType::get(Ty, NumPadBytes);
-
- Elts.push_back(llvm::Constant::getNullValue(Ty));
- Types.push_back(Ty);
- }
-
- llvm::StructType* STy = llvm::StructType::get(Types, false);
- return llvm::ConstantStruct::get(STy, Elts);
- }
-
+
llvm::Constant *EmitUnionInitialization(InitListExpr *ILE) {
return ConstStructBuilder::BuildStruct(CGM, CGF, ILE);
-
- const llvm::Type *Ty = ConvertType(ILE->getType());
-
- FieldDecl* curField = ILE->getInitializedFieldInUnion();
- if (!curField) {
- // There's no field to initialize, so value-initialize the union.
-#ifndef NDEBUG
- // Make sure that it's really an empty and not a failure of
- // semantic analysis.
- RecordDecl *RD = ILE->getType()->getAs<RecordType>()->getDecl();
- for (RecordDecl::field_iterator Field = RD->field_begin(),
- FieldEnd = RD->field_end();
- Field != FieldEnd; ++Field)
- assert(Field->isUnnamedBitfield() && "Only unnamed bitfields allowed");
-#endif
- return llvm::Constant::getNullValue(Ty);
- }
-
- if (curField->isBitField()) {
- // Create a dummy struct for bit-field insertion
- unsigned NumElts = CGM.getTargetData().getTypeAllocSize(Ty);
- llvm::Constant* NV =
- llvm::Constant::getNullValue(llvm::Type::Int8Ty);
- std::vector<llvm::Constant*> Elts(NumElts, NV);
-
- InsertBitfieldIntoStruct(Elts, curField, ILE->getInit(0));
- const llvm::ArrayType *RetTy =
- llvm::ArrayType::get(NV->getType(), NumElts);
- return llvm::ConstantArray::get(RetTy, Elts);
- }
-
- llvm::Constant *InitElem;
- if (ILE->getNumInits() > 0) {
- Expr *Init = ILE->getInit(0);
- InitElem = CGM.EmitConstantExpr(Init, Init->getType(), CGF);
- } else {
- InitElem = CGM.EmitNullConstant(curField->getType());
- }
- return EmitUnion(InitElem, Ty);
}
llvm::Constant *EmitVectorInitialization(InitListExpr *ILE) {
More information about the cfe-commits
mailing list