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[CIR] Fix alignment when lowering set/get bitfield operations #148999

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Merged
merged 3 commits into from
Jul 18, 2025
Merged

[CIR] Fix alignment when lowering set/get bitfield operations #148999

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266483e
[CIR] Fix alignment when lowering set/get bitfield operations
Andres-Salamanca Jul 16, 2025
90dde10
Address review comments
Andres-Salamanca Jul 16, 2025
6001b12
Remove useVolatile to be added later
Andres-Salamanca Jul 18, 2025
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14 changes: 4 additions & 10 deletions clang/include/clang/CIR/Dialect/IR/CIROps.td
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Original file line number Diff line number Diff line change
Expand Up @@ -1729,7 +1729,7 @@ def SetBitfieldOp : CIR_Op<"set_bitfield"> {
Arg<CIR_PointerType, "the address to store the value", [MemWrite]>:$addr,
CIR_AnyType:$src,
BitfieldInfoAttr:$bitfield_info,
OptionalAttr<I64Attr>:$alignment,
DefaultValuedOptionalAttr<I64Attr, "0">:$alignment,
UnitAttr:$is_volatile
);

Expand Down Expand Up @@ -1757,10 +1757,7 @@ def SetBitfieldOp : CIR_Op<"set_bitfield"> {
BitfieldInfoAttr::get($_builder.getContext(),
name, storage_type,
size, offset, is_signed);
build($_builder, $_state, type, addr, src, info,
alignment == 0 ? IntegerAttr()
: $_builder.getI64IntegerAttr(alignment),
is_volatile);
build($_builder, $_state, type, addr, src, info, alignment, is_volatile);
}]>
];
}
Expand Down Expand Up @@ -1819,7 +1816,7 @@ def GetBitfieldOp : CIR_Op<"get_bitfield"> {
let arguments = (ins
Arg<CIR_PointerType, "the address to load from", [MemRead]>:$addr,
BitfieldInfoAttr:$bitfield_info,
OptionalAttr<I64Attr>:$alignment,
DefaultValuedOptionalAttr<I64Attr, "0">:$alignment,
UnitAttr:$is_volatile
);

Expand All @@ -1846,10 +1843,7 @@ def GetBitfieldOp : CIR_Op<"get_bitfield"> {
BitfieldInfoAttr::get($_builder.getContext(),
name, storage_type,
size, offset, is_signed);
build($_builder, $_state, type, addr, info,
alignment == 0 ? IntegerAttr()
: $_builder.getI64IntegerAttr(alignment),
is_volatile);
build($_builder, $_state, type, addr, info, alignment, is_volatile);
}]>
];
}
Expand Down
20 changes: 10 additions & 10 deletions clang/lib/CIR/CodeGen/CIRGenBuilder.h
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Expand Up @@ -424,23 +424,23 @@ class CIRGenBuilderTy : public cir::CIRBaseBuilderTy {
}

mlir::Value createSetBitfield(mlir::Location loc, mlir::Type resultType,
mlir::Value dstAddr, mlir::Type storageType,
Address dstAddr, mlir::Type storageType,
mlir::Value src, const CIRGenBitFieldInfo &info,
bool isLvalueVolatile, bool useVolatile,
unsigned alignment = 0) {
bool isLvalueVolatile, bool useVolatile) {
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@xlauko xlauko Jul 18, 2025

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useVolatile is never used can we remove it? We can always add it later.

return create<cir::SetBitfieldOp>(
loc, resultType, dstAddr, storageType, src, info.name, info.size,
info.offset, info.isSigned, isLvalueVolatile, alignment);
loc, resultType, dstAddr.getPointer(), storageType, src, info.name,
info.size, info.offset, info.isSigned, isLvalueVolatile,
dstAddr.getAlignment().getAsAlign().value());
}

mlir::Value createGetBitfield(mlir::Location loc, mlir::Type resultType,
mlir::Value addr, mlir::Type storageType,
Address addr, mlir::Type storageType,
const CIRGenBitFieldInfo &info,
bool isLvalueVolatile, bool useVolatile,
unsigned alignment = 0) {
bool isLvalueVolatile, bool useVolatile) {
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@xlauko xlauko Jul 18, 2025

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useVolatile is never used can we remove it? We can always add it later.

return create<cir::GetBitfieldOp>(
loc, resultType, addr, storageType, info.name, info.size, info.offset,
info.isSigned, isLvalueVolatile, alignment);
loc, resultType, addr.getPointer(), storageType, info.name, info.size,
info.offset, info.isSigned, isLvalueVolatile,
addr.getAlignment().getAsAlign().value());
}
};

Expand Down
13 changes: 6 additions & 7 deletions clang/lib/CIR/CodeGen/CIRGenExpr.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -337,10 +337,9 @@ mlir::Value CIRGenFunction::emitStoreThroughBitfieldLValue(RValue src,

mlir::Value dstAddr = dst.getAddress().getPointer();

return builder.createSetBitfield(
dstAddr.getLoc(), resLTy, dstAddr, ptr.getElementType(), src.getValue(),
info, dst.isVolatileQualified(), useVolatile,
dst.getAddress().getAlignment().getAsAlign().value());
return builder.createSetBitfield(dstAddr.getLoc(), resLTy, ptr,
ptr.getElementType(), src.getValue(), info,
dst.isVolatileQualified(), useVolatile);
}

RValue CIRGenFunction::emitLoadOfBitfieldLValue(LValue lv, SourceLocation loc) {
Expand All @@ -352,9 +351,9 @@ RValue CIRGenFunction::emitLoadOfBitfieldLValue(LValue lv, SourceLocation loc) {

assert(!cir::MissingFeatures::armComputeVolatileBitfields());

mlir::Value field = builder.createGetBitfield(
getLoc(loc), resLTy, ptr.getPointer(), ptr.getElementType(), info,
lv.isVolatile(), false, ptr.getAlignment().getAsAlign().value());
mlir::Value field =
builder.createGetBitfield(getLoc(loc), resLTy, ptr, ptr.getElementType(),
info, lv.isVolatile(), false);
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@xlauko xlauko Jul 18, 2025

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If the argument is to stay add comment to /*useVolatile=*/ false please, but we should remove it entirely as noted before.

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@Andres-Salamanca Andres-Salamanca Jul 18, 2025

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Done

assert(!cir::MissingFeatures::opLoadEmitScalarRangeCheck() && "NYI");
return RValue::get(field);
}
Expand Down
7 changes: 3 additions & 4 deletions clang/lib/CIR/Lowering/DirectToLLVM/LowerToLLVM.cpp
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Expand Up @@ -2555,7 +2555,7 @@ mlir::LogicalResult CIRToLLVMSetBitfieldOpLowering::matchAndRewrite(
assert(storageSize > size && "Invalid bitfield size.");

mlir::Value val = rewriter.create<mlir::LLVM::LoadOp>(
op.getLoc(), intType, adaptor.getAddr(), op.getAlignment().value(),
op.getLoc(), intType, adaptor.getAddr(), op.getAlignment(),
op.getIsVolatile());

srcVal =
Expand All @@ -2572,8 +2572,7 @@ mlir::LogicalResult CIRToLLVMSetBitfieldOpLowering::matchAndRewrite(
}

rewriter.create<mlir::LLVM::StoreOp>(op.getLoc(), srcVal, adaptor.getAddr(),
op.getAlignment().value(),
op.getIsVolatile());
op.getAlignment(), op.getIsVolatile());

mlir::Type resultTy = getTypeConverter()->convertType(op.getType());

Expand Down Expand Up @@ -2647,7 +2646,7 @@ mlir::LogicalResult CIRToLLVMGetBitfieldOpLowering::matchAndRewrite(
computeBitfieldIntType(storageType, context, storageSize);

mlir::Value val = rewriter.create<mlir::LLVM::LoadOp>(
op.getLoc(), intType, adaptor.getAddr(), op.getAlignment().value(),
op.getLoc(), intType, adaptor.getAddr(), op.getAlignment(),
op.getIsVolatile());
val = rewriter.create<mlir::LLVM::BitcastOp>(op.getLoc(), intType, val);

Expand Down