OS << ")\n";
}
+// Dynamically round a pointer up to a multiple of the given alignment.
+static llvm::Value *emitRoundPointerUpToAlignment(CodeGenFunction &CGF,
+ llvm::Value *Ptr,
+ CharUnits Align) {
+ llvm::Value *PtrAsInt = Ptr;
+ // OverflowArgArea = (OverflowArgArea + Align - 1) & -Align;
+ PtrAsInt = CGF.Builder.CreatePtrToInt(PtrAsInt, CGF.IntPtrTy);
+ PtrAsInt = CGF.Builder.CreateAdd(PtrAsInt,
+ llvm::ConstantInt::get(CGF.IntPtrTy, Align.getQuantity() - 1));
+ PtrAsInt = CGF.Builder.CreateAnd(PtrAsInt,
+ llvm::ConstantInt::get(CGF.IntPtrTy, -Align.getQuantity()));
+ PtrAsInt = CGF.Builder.CreateIntToPtr(PtrAsInt,
+ Ptr->getType(),
+ Ptr->getName() + ".aligned");
+ return PtrAsInt;
+}
+
/// Emit va_arg for a platform using the common void* representation,
/// where arguments are simply emitted in an array of slots on the stack.
///
// If the CC aligns values higher than the slot size, do so if needed.
Address Addr = Address::invalid();
if (AllowHigherAlign && DirectAlign > SlotSize) {
- llvm::Value *PtrAsInt = Ptr;
- PtrAsInt = CGF.Builder.CreatePtrToInt(PtrAsInt, CGF.IntPtrTy);
- PtrAsInt = CGF.Builder.CreateAdd(PtrAsInt,
- llvm::ConstantInt::get(CGF.IntPtrTy, DirectAlign.getQuantity() - 1));
- PtrAsInt = CGF.Builder.CreateAnd(PtrAsInt,
- llvm::ConstantInt::get(CGF.IntPtrTy, -DirectAlign.getQuantity()));
- Addr = Address(CGF.Builder.CreateIntToPtr(PtrAsInt, Ptr->getType(),
- "argp.cur.aligned"),
- DirectAlign);
+ Addr = Address(emitRoundPointerUpToAlignment(CGF, Ptr, DirectAlign),
+ DirectAlign);
} else {
- Addr = Address(Ptr, SlotSize);
+ Addr = Address(Ptr, SlotSize);
}
// Advance the pointer past the argument, then store that back.
// byte boundary if alignment needed by type exceeds 8 byte boundary.
// It isn't stated explicitly in the standard, but in practice we use
// alignment greater than 16 where necessary.
- uint64_t Align = CGF.getContext().getTypeAlignInChars(Ty).getQuantity();
- if (Align > 8) {
- // overflow_arg_area = (overflow_arg_area + align - 1) & -align;
- llvm::Value *Offset =
- llvm::ConstantInt::get(CGF.Int64Ty, Align - 1);
- overflow_arg_area = CGF.Builder.CreateGEP(overflow_arg_area, Offset);
- llvm::Value *AsInt = CGF.Builder.CreatePtrToInt(overflow_arg_area,
- CGF.Int64Ty);
- llvm::Value *Mask = llvm::ConstantInt::get(CGF.Int64Ty, -(uint64_t)Align);
- overflow_arg_area =
- CGF.Builder.CreateIntToPtr(CGF.Builder.CreateAnd(AsInt, Mask),
- overflow_arg_area->getType(),
- "overflow_arg_area.align");
+ CharUnits Align = CGF.getContext().getTypeAlignInChars(Ty);
+ if (Align > CharUnits::fromQuantity(8)) {
+ overflow_arg_area = emitRoundPointerUpToAlignment(CGF, overflow_arg_area,
+ Align);
}
// AMD64-ABI 3.5.7p5: Step 8. Fetch type from l->overflow_arg_area.
CGF.Builder.CreateStore(overflow_arg_area, overflow_arg_area_p);
// AMD64-ABI 3.5.7p5: Step 11. Return the fetched type.
- return Address(Res, CharUnits::fromQuantity(Align));
+ return Address(Res, Align);
}
Address X86_64ABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
Address OverflowAreaAddr =
Builder.CreateStructGEP(VAList, 3, CharUnits::fromQuantity(4));
- Address OverflowArea(Builder.CreateLoad(OverflowAreaAddr),
+ Address OverflowArea(Builder.CreateLoad(OverflowAreaAddr, "argp.cur"),
OverflowAreaAlign);
-
- // The current address is the address of the varargs element.
- // FIXME: do we not need to round up to alignment?
+ // Round up address of argument to alignment
+ CharUnits Align = CGF.getContext().getTypeAlignInChars(Ty);
+ if (Align > OverflowAreaAlign) {
+ llvm::Value *Ptr = OverflowArea.getPointer();
+ OverflowArea = Address(emitRoundPointerUpToAlignment(CGF, Ptr, Align),
+ Align);
+ }
+
MemAddr = Builder.CreateElementBitCast(OverflowArea, DirectTy);
// Increase the overflow area.
// CHECK-PPC:[[USING_OVERFLOW]]
// CHECK-PPC-NEXT: [[OVERFLOW_AREA_P:%[0-9]+]] = getelementptr inbounds %struct.__va_list_tag, %struct.__va_list_tag* [[ARRAYDECAY]], i32 0, i32 3
// CHECK-PPC-NEXT: [[OVERFLOW_AREA:%.+]] = load i8*, i8** [[OVERFLOW_AREA_P]], align 4
-// CHECK-PPC-NEXT: [[MEMADDR:%.+]] = bitcast i8* [[OVERFLOW_AREA]] to %struct.x**
-// CHECK-PPC-NEXT: [[NEW_OVERFLOW_AREA:%[0-9]+]] = getelementptr inbounds i8, i8* [[OVERFLOW_AREA]], i32 4
-// CHECK-PPC-NEXT: store i8* [[NEW_OVERFLOW_AREA]], i8** [[OVERFLOW_AREA_P]]
+// CHECK-PPC-NEXT: %{{[0-9]+}} = ptrtoint i8* %argp.cur to i32
+// CHECK-PPC-NEXT: %{{[0-9]+}} = add i32 %{{[0-9]+}}, 7
+// CHECK-PPC-NEXT: %{{[0-9]+}} = and i32 %{{[0-9]+}}, -8
+// CHECK-PPC-NEXT: %argp.cur.aligned = inttoptr i32 %{{[0-9]+}} to i8*
+// CHECK-PPC-NEXT: [[MEMADDR:%.+]] = bitcast i8* %argp.cur.aligned to %struct.x**
+// CHECK-PPC-NEXT: [[NEW_OVERFLOW_AREA:%[0-9]+]] = getelementptr inbounds i8, i8* %argp.cur.aligned, i32 4
+// CHECK-PPC-NEXT: store i8* [[NEW_OVERFLOW_AREA:%[0-9]+]], i8** [[OVERFLOW_AREA_P]], align 4
// CHECK-PPC-NEXT: br label %[[CONT]]
//
// CHECK-PPC:[[CONT]]