[clang] Add AVR specific inline assembly escaped characters

[benshi001]

Summary

Fixes https://github.com/llvm/llvm-project/issues/60204

[jacquesguan]

clang/lib/Basic/Targets/AVR.cpp

433

redundant variable?

[benshi001]

clang/lib/Basic/Targets/AVR.cpp

433

Removed. Thanks!

[jacquesguan]

LGTM.

clang/lib/Basic/Targets/AVR.h

IntType getLeastIntTypeByWidth(unsigned BitWidth, bool IsSigned) const final {
     return BitWidth == 16
                ? (IsSigned ? SignedInt : UnsignedInt)
                : TargetInfo::getLeastIntTypeByWidth(BitWidth, IsSigned);
   }
 
   bool isValidCPUName(StringRef Name) const override;
   void fillValidCPUList(SmallVectorImpl<StringRef> &Values) const override;
   bool setCPU(const std::string &Name) override;
+  std::optional<std::string> handleAsmEscapedChar(char EscChar) const override;
   StringRef getABI() const override { return ABI; }
 
 protected:
   std::string CPU;
   StringRef ABI;
   StringRef DefineName;
   StringRef Arch;
   int NumFlashBanks = 0;
 };
 
 } // namespace targets
 } // namespace clang
 
 #endif // LLVM_CLANG_LIB_BASIC_TARGETS_AVR_H

clang/lib/Basic/Targets/AVR.cpp

if (It != std::end(AVRMcus)) {
     NumFlashBanks = It->NumFlashBanks;
     return true;
   }
 
   // Parameter Name is neither valid family name nor valid device name.
   return false;
 }
 
+std::optional<std::string>
+AVRTargetInfo::handleAsmEscapedChar(char EscChar) const {
+  switch (EscChar) {
+  // "%~" represents for 'r' depends on the device has long jump/call.
+  case '~':
+    return ArchHasJMPCALL(Arch) ? std::string("") : std::string(1, 'r');
+
+  // "%!" represents for 'e' depends on the PC register size.
+  case '!':
+    return ArchHas3BytePC(Arch) ? std::string(1, 'e') : std::string("");
+
+  // This is an invalid escape character for AVR.
+  default:
+    return std::nullopt;
+  }
+}
+
 void AVRTargetInfo::getTargetDefines(const LangOptions &Opts,
                                      MacroBuilder &Builder) const {
   Builder.defineMacro("AVR");
   Builder.defineMacro("__AVR");
   Builder.defineMacro("__AVR__");
   Builder.defineMacro("__ELF__");
 
   if (ABI == "avrtiny")

clang/test/CodeGen/avr/avr-inline-asm-constraints.c

 // REQUIRES: avr-registered-target
-// RUN: %clang_cc1 -triple avr-unknown-unknown -emit-llvm -o - %s | FileCheck %s
+// RUN: %clang_cc1 -x c -triple avr -target-cpu at90s8515 -emit-llvm -o - %s \
+// RUN:     | FileCheck --check-prefixes=CHECK,AVR25 %s
+// RUN: %clang_cc1 -x c -triple avr -target-cpu atmega328 -emit-llvm -o - %s \
+// RUN:     | FileCheck --check-prefixes=CHECK,AVR51 %s
+// RUN: %clang_cc1 -x c -triple avr -target-cpu atmega2560 -emit-llvm -o - %s \
+// RUN:     | FileCheck --check-prefixes=CHECK,AVR6 %s
 
 int data;
 
 void a() {
   // CHECK: call addrspace(0) void asm sideeffect "add r5, $0", "a"(i16 %0)
   asm("add r5, %0" :: "a"(data));
 }
 
void ra() {
   // CHECK: call addrspace(0) void asm sideeffect "subi r30, $0", "ra"(i16 50)
   asm("subi r30, %0" :: "ra"(50));
 }
 
 void ora() {
   // CHECK: call addrspace(0) i16 asm "subi r30, $0", "=ra"()
   asm("subi r30, %0" : "=ra"(data));
 }
+
+void escapeChar(void) {
+  asm("_foo:");
+  // AVR25: call addrspace(0) void asm sideeffect "rcall _foo"
+  // AVR51: call addrspace(0) void asm sideeffect "call _foo"
+  // AVR6:  call addrspace(0) void asm sideeffect "call _foo"
+  asm("%~call _foo" ::);
+  // AVR25: call addrspace(0) void asm sideeffect "rjmp _foo"
+  // AVR51: call addrspace(0) void asm sideeffect "jmp _foo"
+  // AVR6:  call addrspace(0) void asm sideeffect "jmp _foo"
+  asm("%~jmp _foo" ::);
+  // AVR25: call addrspace(0) void asm sideeffect "icall"
+  // AVR51: call addrspace(0) void asm sideeffect "icall"
+  // AVR6:  call addrspace(0) void asm sideeffect "eicall"
+  asm("%!icall" ::);
+  // AVR25: call addrspace(0) void asm sideeffect "ijmp"
+  // AVR51: call addrspace(0) void asm sideeffect "ijmp"
+  // AVR6:  call addrspace(0) void asm sideeffect "eijmp"
+  asm("%!ijmp" ::);
+}