1 //===- MSP430.cpp ---------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "ABIInfoImpl.h"
10 #include "TargetInfo.h"
11 
12 using namespace clang;
13 using namespace clang::CodeGen;
14 
15 //===----------------------------------------------------------------------===//
16 // MSP430 ABI Implementation
17 //===----------------------------------------------------------------------===//
18 
19 namespace {
20 
21 class MSP430ABIInfo : public DefaultABIInfo {
22   static ABIArgInfo complexArgInfo() {
23     ABIArgInfo Info = ABIArgInfo::getDirect();
24     Info.setCanBeFlattened(false);
25     return Info;
26   }
27 
28 public:
29   MSP430ABIInfo(CodeGenTypes &CGT) : DefaultABIInfo(CGT) {}
30 
31   ABIArgInfo classifyReturnType(QualType RetTy) const {
32     if (RetTy->isAnyComplexType())
33       return complexArgInfo();
34 
35     return DefaultABIInfo::classifyReturnType(RetTy);
36   }
37 
38   ABIArgInfo classifyArgumentType(QualType RetTy) const {
39     if (RetTy->isAnyComplexType())
40       return complexArgInfo();
41 
42     return DefaultABIInfo::classifyArgumentType(RetTy);
43   }
44 
45   // Just copy the original implementations because
46   // DefaultABIInfo::classify{Return,Argument}Type() are not virtual
47   void computeInfo(CGFunctionInfo &FI) const override {
48     if (!getCXXABI().classifyReturnType(FI))
49       FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
50     for (auto &I : FI.arguments())
51       I.info = classifyArgumentType(I.type);
52   }
53 
54   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
55                     QualType Ty) const override {
56     return EmitVAArgInstr(CGF, VAListAddr, Ty, classifyArgumentType(Ty));
57   }
58 };
59 
60 class MSP430TargetCodeGenInfo : public TargetCodeGenInfo {
61 public:
62   MSP430TargetCodeGenInfo(CodeGenTypes &CGT)
63       : TargetCodeGenInfo(std::make_unique<MSP430ABIInfo>(CGT)) {}
64   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
65                            CodeGen::CodeGenModule &M) const override;
66 };
67 
68 }
69 
70 void MSP430TargetCodeGenInfo::setTargetAttributes(
71     const Decl *D, llvm::GlobalValue *GV, CodeGen::CodeGenModule &M) const {
72   if (GV->isDeclaration())
73     return;
74   if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D)) {
75     const auto *InterruptAttr = FD->getAttr<MSP430InterruptAttr>();
76     if (!InterruptAttr)
77       return;
78 
79     // Handle 'interrupt' attribute:
80     llvm::Function *F = cast<llvm::Function>(GV);
81 
82     // Step 1: Set ISR calling convention.
83     F->setCallingConv(llvm::CallingConv::MSP430_INTR);
84 
85     // Step 2: Add attributes goodness.
86     F->addFnAttr(llvm::Attribute::NoInline);
87     F->addFnAttr("interrupt", llvm::utostr(InterruptAttr->getNumber()));
88   }
89 }
90 
91 std::unique_ptr<TargetCodeGenInfo>
92 CodeGen::createMSP430TargetCodeGenInfo(CodeGenModule &CGM) {
93   return std::make_unique<MSP430TargetCodeGenInfo>(CGM.getTypes());
94 }
95