[clang] Add storage for APValue in ConstantExpr
Summary:
When using ConstantExpr we often need the result of the expression to be kept in the AST. Currently this is done on a by the node that needs the result and has been done multiple times for enumerator, for constexpr variables... . This patch adds to ConstantExpr the ability to store the result of evaluating the expression. no functional changes expected.
Changes:
- Add trailling object to ConstantExpr that can hold an APValue or an uint64_t. the uint64_t is here because most ConstantExpr yield integral values so there is an optimized layout for integral values.
- Add basic* serialization support for the trailing result.
- Move conversion functions from an enum to a fltSemantics from clang::FloatingLiteral to llvm::APFloatBase. this change is to make it usable for serializing APValues.
- Add basic* Import support for the trailing result.
- ConstantExpr created in CheckConvertedConstantExpression now stores the result in the ConstantExpr Node.
- Adapt AST dump to print the result when present.
basic* : None, Indeterminate, Int, Float, FixedPoint, ComplexInt, ComplexFloat,
the result is not yet used anywhere but for -ast-dump.
Reviewers: rsmith, martong, shafik
Reviewed By: rsmith
Subscribers: rnkovacs, hiraditya, dexonsmith, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D62399
llvm-svn: 363493
diff --git a/clang/lib/Serialization/ASTReader.cpp b/clang/lib/Serialization/ASTReader.cpp
index 55e1f13..fa4a4b3 100644
--- a/clang/lib/Serialization/ASTReader.cpp
+++ b/clang/lib/Serialization/ASTReader.cpp
@@ -9102,6 +9102,62 @@
return SourceRange(beg, end);
}
+static FixedPointSemantics
+ReadFixedPointSemantics(const SmallVectorImpl<uint64_t> &Record,
+ unsigned &Idx) {
+ unsigned Width = Record[Idx++];
+ unsigned Scale = Record[Idx++];
+ uint64_t Tmp = Record[Idx++];
+ bool IsSigned = Tmp & 0x1;
+ bool IsSaturated = Tmp & 0x2;
+ bool HasUnsignedPadding = Tmp & 0x4;
+ return FixedPointSemantics(Width, Scale, IsSigned, IsSaturated,
+ HasUnsignedPadding);
+}
+
+APValue ASTReader::ReadAPValue(const RecordData &Record, unsigned &Idx) {
+ unsigned Kind = Record[Idx++];
+ switch (Kind) {
+ case APValue::None:
+ return APValue();
+ case APValue::Indeterminate:
+ return APValue::IndeterminateValue();
+ case APValue::Int:
+ return APValue(ReadAPSInt(Record, Idx));
+ case APValue::Float: {
+ const llvm::fltSemantics &FloatSema = llvm::APFloatBase::EnumToSemantics(
+ static_cast<llvm::APFloatBase::Semantics>(Record[Idx++]));
+ return APValue(ReadAPFloat(Record, FloatSema, Idx));
+ }
+ case APValue::FixedPoint: {
+ FixedPointSemantics FPSema = ReadFixedPointSemantics(Record, Idx);
+ return APValue(APFixedPoint(ReadAPInt(Record, Idx), FPSema));
+ }
+ case APValue::ComplexInt: {
+ llvm::APSInt First = ReadAPSInt(Record, Idx);
+ return APValue(std::move(First), ReadAPSInt(Record, Idx));
+ }
+ case APValue::ComplexFloat: {
+ const llvm::fltSemantics &FloatSema1 = llvm::APFloatBase::EnumToSemantics(
+ static_cast<llvm::APFloatBase::Semantics>(Record[Idx++]));
+ llvm::APFloat First = ReadAPFloat(Record, FloatSema1, Idx);
+ const llvm::fltSemantics &FloatSema2 = llvm::APFloatBase::EnumToSemantics(
+ static_cast<llvm::APFloatBase::Semantics>(Record[Idx++]));
+ return APValue(std::move(First), ReadAPFloat(Record, FloatSema2, Idx));
+ }
+ case APValue::LValue:
+ case APValue::Vector:
+ case APValue::Array:
+ case APValue::Struct:
+ case APValue::Union:
+ case APValue::MemberPointer:
+ case APValue::AddrLabelDiff:
+ // TODO : Handle all these APValue::ValueKind.
+ return APValue();
+ }
+ llvm_unreachable("Invalid APValue::ValueKind");
+}
+
/// Read an integral value
llvm::APInt ASTReader::ReadAPInt(const RecordData &Record, unsigned &Idx) {
unsigned BitWidth = Record[Idx++];