Non-allocatable Global Named Register
This patch implements global named registers in Clang, lowering to the just
created intrinsics in LLVM (@llvm.read/write_register). A new type of LValue
had to be created (Register), which just adds support to carry the metadata
node containing the name of the register. Two new methods to emit loads and
stores interoperate with another to emit the named metadata node.
No guarantees are being made and only non-allocatable global variable named
registers are being supported. Local named register support is unchanged.
llvm-svn: 209149
diff --git a/clang/lib/CodeGen/CGValue.h b/clang/lib/CodeGen/CGValue.h
index da2a034..3739ae9 100644
--- a/clang/lib/CodeGen/CGValue.h
+++ b/clang/lib/CodeGen/CGValue.h
@@ -110,7 +110,8 @@
Simple, // This is a normal l-value, use getAddress().
VectorElt, // This is a vector element l-value (V[i]), use getVector*
BitField, // This is a bitfield l-value, use getBitfield*.
- ExtVectorElt // This is an extended vector subset, use getExtVectorComp
+ ExtVectorElt, // This is an extended vector subset, use getExtVectorComp
+ GlobalReg // This is a register l-value, use getGlobalReg()
} LVType;
llvm::Value *V;
@@ -192,6 +193,7 @@
bool isVectorElt() const { return LVType == VectorElt; }
bool isBitField() const { return LVType == BitField; }
bool isExtVectorElt() const { return LVType == ExtVectorElt; }
+ bool isGlobalReg() const { return LVType == GlobalReg; }
bool isVolatileQualified() const { return Quals.hasVolatile(); }
bool isRestrictQualified() const { return Quals.hasRestrict(); }
@@ -286,6 +288,9 @@
return *BitFieldInfo;
}
+ // global register lvalue
+ llvm::Value *getGlobalReg() const { assert(isGlobalReg()); return V; }
+
static LValue MakeAddr(llvm::Value *address, QualType type,
CharUnits alignment, ASTContext &Context,
llvm::MDNode *TBAAInfo = 0) {
@@ -336,6 +341,16 @@
return R;
}
+ static LValue MakeGlobalReg(llvm::Value *Reg,
+ QualType type,
+ CharUnits Alignment) {
+ LValue R;
+ R.LVType = GlobalReg;
+ R.V = Reg;
+ R.Initialize(type, type.getQualifiers(), Alignment);
+ return R;
+ }
+
RValue asAggregateRValue() const {
// FIMXE: Alignment
return RValue::getAggregate(getAddress(), isVolatileQualified());