summaryrefslogtreecommitdiffstats
path: root/clang/lib
diff options
context:
space:
mode:
Diffstat (limited to 'clang/lib')
-rw-r--r--clang/lib/AST/ASTContext.cpp43
-rw-r--r--clang/lib/Basic/FixedPoint.cpp25
-rw-r--r--clang/lib/CodeGen/CGExprScalar.cpp82
-rw-r--r--clang/lib/Sema/SemaExpr.cpp91
4 files changed, 233 insertions, 8 deletions
diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index 21b6f36e9aa..ed203a331d5 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -10485,7 +10485,13 @@ unsigned char ASTContext::getFixedPointIBits(QualType Ty) const {
}
FixedPointSemantics ASTContext::getFixedPointSemantics(QualType Ty) const {
- assert(Ty->isFixedPointType());
+ assert(Ty->isFixedPointType() ||
+ Ty->isIntegerType() && "Can only get the fixed point semantics for a "
+ "fixed point or integer type.");
+ if (Ty->isIntegerType())
+ return FixedPointSemantics::GetIntegerSemantics(getIntWidth(Ty),
+ Ty->isSignedIntegerType());
+
bool isSigned = Ty->isSignedFixedPointType();
return FixedPointSemantics(
static_cast<unsigned>(getTypeSize(Ty)), getFixedPointScale(Ty), isSigned,
@@ -10502,3 +10508,38 @@ APFixedPoint ASTContext::getFixedPointMin(QualType Ty) const {
assert(Ty->isFixedPointType());
return APFixedPoint::getMin(getFixedPointSemantics(Ty));
}
+
+QualType ASTContext::getCorrespondingSignedFixedPointType(QualType Ty) const {
+ assert(Ty->isUnsignedFixedPointType() &&
+ "Expected unsigned fixed point type");
+ const auto *BTy = Ty->getAs<BuiltinType>();
+
+ switch (BTy->getKind()) {
+ case BuiltinType::UShortAccum:
+ return ShortAccumTy;
+ case BuiltinType::UAccum:
+ return AccumTy;
+ case BuiltinType::ULongAccum:
+ return LongAccumTy;
+ case BuiltinType::SatUShortAccum:
+ return SatShortAccumTy;
+ case BuiltinType::SatUAccum:
+ return SatAccumTy;
+ case BuiltinType::SatULongAccum:
+ return SatLongAccumTy;
+ case BuiltinType::UShortFract:
+ return ShortFractTy;
+ case BuiltinType::UFract:
+ return FractTy;
+ case BuiltinType::ULongFract:
+ return LongFractTy;
+ case BuiltinType::SatUShortFract:
+ return SatShortFractTy;
+ case BuiltinType::SatUFract:
+ return SatFractTy;
+ case BuiltinType::SatULongFract:
+ return SatLongFractTy;
+ default:
+ llvm_unreachable("Unexpected unsigned fixed point type");
+ }
+}
diff --git a/clang/lib/Basic/FixedPoint.cpp b/clang/lib/Basic/FixedPoint.cpp
index bfff0fc212e..0aaa9af191d 100644
--- a/clang/lib/Basic/FixedPoint.cpp
+++ b/clang/lib/Basic/FixedPoint.cpp
@@ -112,4 +112,29 @@ APFixedPoint APFixedPoint::getMin(const FixedPointSemantics &Sema) {
return APFixedPoint(Val, Sema);
}
+FixedPointSemantics FixedPointSemantics::getCommonSemantics(
+ const FixedPointSemantics &Other) const {
+ unsigned CommonScale = std::max(getScale(), Other.getScale());
+ unsigned CommonWidth =
+ std::max(getIntegralBits(), Other.getIntegralBits()) + CommonScale;
+
+ bool ResultIsSigned = isSigned() || Other.isSigned();
+ bool ResultIsSaturated = isSaturated() || Other.isSaturated();
+ bool ResultHasUnsignedPadding = false;
+ if (!ResultIsSigned) {
+ // Both are unsigned.
+ ResultHasUnsignedPadding = hasUnsignedPadding() &&
+ Other.hasUnsignedPadding() && !ResultIsSaturated;
+ }
+
+ // If the result is signed, add an extra bit for the sign. Otherwise, if it is
+ // unsigned and has unsigned padding, we only need to add the extra padding
+ // bit back if we are not saturating.
+ if (ResultIsSigned || ResultHasUnsignedPadding)
+ CommonWidth++;
+
+ return FixedPointSemantics(CommonWidth, CommonScale, ResultIsSigned,
+ ResultIsSaturated, ResultHasUnsignedPadding);
+}
+
} // namespace clang
diff --git a/clang/lib/CodeGen/CGExprScalar.cpp b/clang/lib/CodeGen/CGExprScalar.cpp
index 1c14d4c99a2..6b3c78121bf 100644
--- a/clang/lib/CodeGen/CGExprScalar.cpp
+++ b/clang/lib/CodeGen/CGExprScalar.cpp
@@ -125,6 +125,13 @@ struct BinOpInfo {
return CFP->isZero();
return true;
}
+
+ /// Check if either operand is a fixed point type, in which case, this
+ /// operation did not follow usual arithmetic conversion and both operands may
+ /// not be the same.
+ bool isFixedPointBinOp() const {
+ return isa<BinaryOperator>(E) && Ty->isFixedPointType();
+ }
};
static bool MustVisitNullValue(const Expr *E) {
@@ -351,6 +358,9 @@ public:
Value *EmitFixedPointConversion(Value *Src, QualType SrcTy, QualType DstTy,
SourceLocation Loc);
+ Value *EmitFixedPointConversion(Value *Src, FixedPointSemantics &SrcFixedSema,
+ FixedPointSemantics &DstFixedSema,
+ SourceLocation Loc);
/// Emit a conversion from the specified complex type to the specified
/// destination type, where the destination type is an LLVM scalar type.
@@ -729,6 +739,9 @@ public:
return Builder.CreateOr(Ops.LHS, Ops.RHS, "or");
}
+ // Helper functions for fixed point binary operations.
+ Value *EmitFixedPointAdd(const BinOpInfo &Ops);
+
BinOpInfo EmitBinOps(const BinaryOperator *E);
LValue EmitCompoundAssignLValue(const CompoundAssignOperator *E,
Value *(ScalarExprEmitter::*F)(const BinOpInfo &),
@@ -1423,10 +1436,6 @@ Value *ScalarExprEmitter::EmitScalarConversion(Value *Src, QualType SrcType,
Value *ScalarExprEmitter::EmitFixedPointConversion(Value *Src, QualType SrcTy,
QualType DstTy,
SourceLocation Loc) {
- using llvm::APInt;
- using llvm::ConstantInt;
- using llvm::Value;
-
assert(SrcTy->isFixedPointType());
assert(DstTy->isFixedPointType());
@@ -1434,6 +1443,16 @@ Value *ScalarExprEmitter::EmitFixedPointConversion(Value *Src, QualType SrcTy,
CGF.getContext().getFixedPointSemantics(SrcTy);
FixedPointSemantics DstFPSema =
CGF.getContext().getFixedPointSemantics(DstTy);
+ return EmitFixedPointConversion(Src, SrcFPSema, DstFPSema, Loc);
+}
+
+Value *ScalarExprEmitter::EmitFixedPointConversion(
+ Value *Src, FixedPointSemantics &SrcFPSema, FixedPointSemantics &DstFPSema,
+ SourceLocation Loc) {
+ using llvm::APInt;
+ using llvm::ConstantInt;
+ using llvm::Value;
+
unsigned SrcWidth = SrcFPSema.getWidth();
unsigned DstWidth = DstFPSema.getWidth();
unsigned SrcScale = SrcFPSema.getScale();
@@ -1462,7 +1481,8 @@ Value *ScalarExprEmitter::EmitFixedPointConversion(Value *Src, QualType SrcTy,
} else {
// Adjust the number of fractional bits.
if (DstScale > SrcScale) {
- ResultWidth = SrcWidth + DstScale - SrcScale;
+ // Compare to DstWidth to prevent resizing twice.
+ ResultWidth = std::max(SrcWidth + DstScale - SrcScale, DstWidth);
llvm::Type *UpscaledTy = Builder.getIntNTy(ResultWidth);
Result = Builder.CreateIntCast(Result, UpscaledTy, SrcIsSigned, "resize");
Result = Builder.CreateShl(Result, DstScale - SrcScale, "upscale");
@@ -1493,7 +1513,8 @@ Value *ScalarExprEmitter::EmitFixedPointConversion(Value *Src, QualType SrcTy,
}
// Resize the integer part to get the final destination size.
- Result = Builder.CreateIntCast(Result, DstIntTy, SrcIsSigned, "resize");
+ if (ResultWidth != DstWidth)
+ Result = Builder.CreateIntCast(Result, DstIntTy, SrcIsSigned, "resize");
}
return Result;
}
@@ -3338,9 +3359,58 @@ Value *ScalarExprEmitter::EmitAdd(const BinOpInfo &op) {
return propagateFMFlags(V, op);
}
+ if (op.isFixedPointBinOp())
+ return EmitFixedPointAdd(op);
+
return Builder.CreateAdd(op.LHS, op.RHS, "add");
}
+/// The resulting value must be calculated with exact precision, so the operands
+/// may not be the same type.
+Value *ScalarExprEmitter::EmitFixedPointAdd(const BinOpInfo &op) {
+ using llvm::APSInt;
+ using llvm::ConstantInt;
+
+ const auto *BinOp = cast<BinaryOperator>(op.E);
+ assert(BinOp->getOpcode() == BO_Add && "Expected operation to be addition");
+
+ // The result is a fixed point type and at least one of the operands is fixed
+ // point while the other is either fixed point or an int. This resulting type
+ // should be determined by Sema::handleFixedPointConversions().
+ QualType ResultTy = op.Ty;
+ QualType LHSTy = BinOp->getLHS()->getType();
+ QualType RHSTy = BinOp->getRHS()->getType();
+ ASTContext &Ctx = CGF.getContext();
+ Value *LHS = op.LHS;
+ Value *RHS = op.RHS;
+
+ auto LHSFixedSema = Ctx.getFixedPointSemantics(LHSTy);
+ auto RHSFixedSema = Ctx.getFixedPointSemantics(RHSTy);
+ auto ResultFixedSema = Ctx.getFixedPointSemantics(ResultTy);
+ auto CommonFixedSema = LHSFixedSema.getCommonSemantics(RHSFixedSema);
+
+ // Convert the operands to the full precision type.
+ Value *FullLHS = EmitFixedPointConversion(LHS, LHSFixedSema, CommonFixedSema,
+ BinOp->getExprLoc());
+ Value *FullRHS = EmitFixedPointConversion(RHS, RHSFixedSema, CommonFixedSema,
+ BinOp->getExprLoc());
+
+ // Perform the actual addition.
+ Value *Result;
+ if (ResultFixedSema.isSaturated()) {
+ llvm::Intrinsic::ID IID = ResultFixedSema.isSigned()
+ ? llvm::Intrinsic::sadd_sat
+ : llvm::Intrinsic::uadd_sat;
+ Result = Builder.CreateBinaryIntrinsic(IID, FullLHS, FullRHS);
+ } else {
+ Result = Builder.CreateAdd(FullLHS, FullRHS);
+ }
+
+ // Convert to the result type.
+ return EmitFixedPointConversion(Result, CommonFixedSema, ResultFixedSema,
+ BinOp->getExprLoc());
+}
+
Value *ScalarExprEmitter::EmitSub(const BinOpInfo &op) {
// The LHS is always a pointer if either side is.
if (!op.LHS->getType()->isPointerTy()) {
diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index d5416d4d057..533b3b7da9f 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -1250,6 +1250,93 @@ static QualType handleComplexIntConversion(Sema &S, ExprResult &LHS,
return ComplexType;
}
+/// Return the rank of a given fixed point or integer type. The value itself
+/// doesn't matter, but the values must be increasing with proper increasing
+/// rank as described in N1169 4.1.1.
+static unsigned GetFixedPointRank(QualType Ty) {
+ const auto *BTy = Ty->getAs<BuiltinType>();
+ assert(BTy && "Expected a builtin type.");
+
+ switch (BTy->getKind()) {
+ case BuiltinType::ShortFract:
+ case BuiltinType::UShortFract:
+ case BuiltinType::SatShortFract:
+ case BuiltinType::SatUShortFract:
+ return 1;
+ case BuiltinType::Fract:
+ case BuiltinType::UFract:
+ case BuiltinType::SatFract:
+ case BuiltinType::SatUFract:
+ return 2;
+ case BuiltinType::LongFract:
+ case BuiltinType::ULongFract:
+ case BuiltinType::SatLongFract:
+ case BuiltinType::SatULongFract:
+ return 3;
+ case BuiltinType::ShortAccum:
+ case BuiltinType::UShortAccum:
+ case BuiltinType::SatShortAccum:
+ case BuiltinType::SatUShortAccum:
+ return 4;
+ case BuiltinType::Accum:
+ case BuiltinType::UAccum:
+ case BuiltinType::SatAccum:
+ case BuiltinType::SatUAccum:
+ return 5;
+ case BuiltinType::LongAccum:
+ case BuiltinType::ULongAccum:
+ case BuiltinType::SatLongAccum:
+ case BuiltinType::SatULongAccum:
+ return 6;
+ default:
+ if (BTy->isInteger())
+ return 0;
+ llvm_unreachable("Unexpected fixed point or integer type");
+ }
+}
+
+/// handleFixedPointConversion - Fixed point operations between fixed
+/// point types and integers or other fixed point types do not fall under
+/// usual arithmetic conversion since these conversions could result in loss
+/// of precsision (N1169 4.1.4). These operations should be calculated with
+/// the full precision of their result type (N1169 4.1.6.2.1).
+static QualType handleFixedPointConversion(Sema &S, QualType LHSTy,
+ QualType RHSTy) {
+ assert((LHSTy->isFixedPointType() || RHSTy->isFixedPointType()) &&
+ "Expected at least one of the operands to be a fixed point type");
+ assert((LHSTy->isFixedPointOrIntegerType() ||
+ RHSTy->isFixedPointOrIntegerType()) &&
+ "Special fixed point arithmetic operation conversions are only "
+ "applied to ints or other fixed point types");
+
+ // If one operand has signed fixed-point type and the other operand has
+ // unsigned fixed-point type, then the unsigned fixed-point operand is
+ // converted to its corresponding signed fixed-point type and the resulting
+ // type is the type of the converted operand.
+ if (RHSTy->isSignedFixedPointType() && LHSTy->isUnsignedFixedPointType())
+ LHSTy = S.Context.getCorrespondingSignedFixedPointType(LHSTy);
+ else if (RHSTy->isUnsignedFixedPointType() && LHSTy->isSignedFixedPointType())
+ RHSTy = S.Context.getCorrespondingSignedFixedPointType(RHSTy);
+
+ // The result type is the type with the highest rank, whereby a fixed-point
+ // conversion rank is always greater than an integer conversion rank; if the
+ // type of either of the operands is a saturating fixedpoint type, the result
+ // type shall be the saturating fixed-point type corresponding to the type
+ // with the highest rank; the resulting value is converted (taking into
+ // account rounding and overflow) to the precision of the resulting type.
+ // Same ranks between signed and unsigned types are resolved earlier, so both
+ // types are either signed or both unsigned at this point.
+ unsigned LHSTyRank = GetFixedPointRank(LHSTy);
+ unsigned RHSTyRank = GetFixedPointRank(RHSTy);
+
+ QualType ResultTy = LHSTyRank > RHSTyRank ? LHSTy : RHSTy;
+
+ if (LHSTy->isSaturatedFixedPointType() || RHSTy->isSaturatedFixedPointType())
+ ResultTy = S.Context.getCorrespondingSaturatedType(ResultTy);
+
+ return ResultTy;
+}
+
/// UsualArithmeticConversions - Performs various conversions that are common to
/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this
/// routine returns the first non-arithmetic type found. The client is
@@ -1322,12 +1409,14 @@ QualType Sema::UsualArithmeticConversions(ExprResult &LHS, ExprResult &RHS,
return handleComplexIntConversion(*this, LHS, RHS, LHSType, RHSType,
IsCompAssign);
+ if (LHSType->isFixedPointType() || RHSType->isFixedPointType())
+ return handleFixedPointConversion(*this, LHSType, RHSType);
+
// Finally, we have two differing integer types.
return handleIntegerConversion<doIntegralCast, doIntegralCast>
(*this, LHS, RHS, LHSType, RHSType, IsCompAssign);
}
-
//===----------------------------------------------------------------------===//
// Semantic Analysis for various Expression Types
//===----------------------------------------------------------------------===//
OpenPOWER on IntegriCloud