1 //===- M68k.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 // M68k ABI Implementation
17 //===----------------------------------------------------------------------===//
18 
19 namespace {
20 
21 class M68kTargetCodeGenInfo : public TargetCodeGenInfo {
22 public:
23   M68kTargetCodeGenInfo(CodeGenTypes &CGT)
24       : TargetCodeGenInfo(std::make_unique<DefaultABIInfo>(CGT)) {}
25   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
26                            CodeGen::CodeGenModule &M) const override;
27 };
28 
29 } // namespace
30 
31 void M68kTargetCodeGenInfo::setTargetAttributes(
32     const Decl *D, llvm::GlobalValue *GV, CodeGen::CodeGenModule &M) const {
33   if (const auto *FD = dyn_cast_or_null<FunctionDecl>(D)) {
34     if (const auto *attr = FD->getAttr<M68kInterruptAttr>()) {
35       // Handle 'interrupt' attribute:
36       llvm::Function *F = cast<llvm::Function>(GV);
37 
38       // Step 1: Set ISR calling convention.
39       F->setCallingConv(llvm::CallingConv::M68k_INTR);
40 
41       // Step 2: Add attributes goodness.
42       F->addFnAttr(llvm::Attribute::NoInline);
43 
44       // Step 3: Emit ISR vector alias.
45       unsigned Num = attr->getNumber() / 2;
46       llvm::GlobalAlias::create(llvm::Function::ExternalLinkage,
47                                 "__isr_" + Twine(Num), F);
48     }
49   }
50 }
51 
52 std::unique_ptr<TargetCodeGenInfo>
53 CodeGen::createM68kTargetCodeGenInfo(CodeGenModule &CGM) {
54   return std::make_unique<M68kTargetCodeGenInfo>(CGM.getTypes());
55 }
56