clang/lib/CodeGen/Targets/MSP430.cpp

   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   RValue EmitVAArg(CodeGenFunction &CGF, Address VAListAddr, QualType Ty,
  55                    AggValueSlot Slot) const override {
  56     return CGF.EmitLoadOfAnyValue(
  57         CGF.MakeAddrLValue(
  58             EmitVAArgInstr(CGF, VAListAddr, Ty, classifyArgumentType(Ty)), Ty),
  59         Slot);
  60   }
  61 };
  62
  63 class MSP430TargetCodeGenInfo : public TargetCodeGenInfo {
  64 public:
  65   MSP430TargetCodeGenInfo(CodeGenTypes &CGT)
  66       : TargetCodeGenInfo(std::make_unique<MSP430ABIInfo>(CGT)) {}
  67   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
  68                            CodeGen::CodeGenModule &M) const override;
  69 };
  70
  71 }
  72
  73 void MSP430TargetCodeGenInfo::setTargetAttributes(
  74     const Decl *D, llvm::GlobalValue *GV, CodeGen::CodeGenModule &M) const {
  75   if (GV->isDeclaration())
  76     return;
  77   if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D)) {
  78     const auto *InterruptAttr = FD->getAttr<MSP430InterruptAttr>();
  79     if (!InterruptAttr)
  80       return;
  81
  82     // Handle 'interrupt' attribute:
  83     llvm::Function *F = cast<llvm::Function>(GV);
  84
  85     // Step 1: Set ISR calling convention.
  86     F->setCallingConv(llvm::CallingConv::MSP430_INTR);
  87
  88     // Step 2: Add attributes goodness.
  89     F->addFnAttr(llvm::Attribute::NoInline);
  90     F->addFnAttr("interrupt", llvm::utostr(InterruptAttr->getNumber()));
  91   }
  92 }
  93
  94 std::unique_ptr<TargetCodeGenInfo>
  95 CodeGen::createMSP430TargetCodeGenInfo(CodeGenModule &CGM) {
  96   return std::make_unique<MSP430TargetCodeGenInfo>(CGM.getTypes());
  97 }