Add armv4t for GBA programming (#73005)

Author: Harlan Haskins

cmake/modules/SwiftSetIfArchBitness.cmake

@@ -9,6 +9,7 @@ function(set_if_arch_bitness var_name)
   if("${SIA_ARCH}" STREQUAL "i386" OR
      "${SIA_ARCH}" STREQUAL "i686" OR
      "${SIA_ARCH}" STREQUAL "x86" OR
+     "${SIA_ARCH}" STREQUAL "armv4t" OR
      "${SIA_ARCH}" STREQUAL "armv5" OR
      "${SIA_ARCH}" STREQUAL "armv6" OR
      "${SIA_ARCH}" STREQUAL "armv6m" OR

lib/IDETool/CompilerInvocation.cpp

@@ -60,6 +60,8 @@ static std::string adjustClangTriple(StringRef TripleStr) {
     OS << "armv5"; break;
   case llvm::Triple::SubArchType::ARMSubArch_v5te:
     OS << "armv5te"; break;
+  case llvm::Triple::SubArchType::ARMSubArch_v4t:
+    OS << "armv4t"; break;
   default:
     // Adjust i386-macosx to x86_64 because there is no Swift stdlib for i386.
     if ((Triple.getOS() == llvm::Triple::MacOSX ||

stdlib/public/CMakeLists.txt

@@ -183,6 +183,7 @@ if(SWIFT_SHOULD_BUILD_EMBEDDED_STDLIB)
   # the following are all ELF targets
   if("ARM" IN_LIST LLVM_TARGETS_TO_BUILD)
     list(APPEND EMBEDDED_STDLIB_TARGET_TRIPLES
+      "armv4t   armv4t-none-none-eabi     armv4t-none-none-eabi"
       "armv6    armv6-none-none-eabi      armv6-none-none-eabi"
       "armv6m   armv6m-none-none-eabi     armv6m-none-none-eabi"
       "armv7    armv7-none-none-eabi      armv7-none-none-eabi"