From a71b028a0f29b82b187e789889782b55dfc044d9 Mon Sep 17 00:00:00 2001
From: Tomas Lindquist Olsen <tomas.l.olsen@gmail.com>
Date: Sun, 1 Mar 2009 22:27:03 +0100
Subject: [PATCH] Implemented basic -m32 and -m64 options.

---
 CMakeLists.txt     |  8 ++++++++
 gen/cl_options.cpp | 11 +++++++----
 gen/cl_options.h   |  2 ++
 gen/main.cpp       | 18 +++++++++++++++++-
 4 files changed, 34 insertions(+), 5 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index eb071f1f..47470db9 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -23,6 +23,11 @@ execute_process(
 	OUTPUT_VARIABLE HOST_TARGET
 	OUTPUT_STRIP_TRAILING_WHITESPACE
 )
+execute_process(
+    COMMAND /bin/sh ${PROJECT_SOURCE_DIR}/find-alt-triple.sh ${HOST_TARGET}
+    OUTPUT_VARIABLE HOST_ALT_TARGET
+    OUTPUT_STRIP_TRAILING_WHITESPACE
+)
 execute_process(
 	COMMAND ${PERL_EXECUTABLE} ${LLVM_CONFIG} --cxxflags
 	OUTPUT_VARIABLE LLVM_CXXFLAGS
@@ -105,6 +110,7 @@ set(LDC_GENERATED
 # idgen and impcnvgen done
 
 set(DEFAULT_TARGET ${HOST_TARGET} CACHE STRING "default target")
+set(DEFAULT_ALT_TARGET ${HOST_ALT_TARGET} CACHE STRING "default alt target")
 
 include_directories(. ${DMDFE_PATH} ${PROJECT_BINARY_DIR}/${DMDFE_PATH} ${LLVM_INSTDIR}/include)
 
@@ -154,8 +160,10 @@ if(CMAKE_MINOR_VERSION LESS 6)
 	set(EXECUTABLE_OUTPUT_PATH ${PROJECT_BINARY_DIR}/bin CACHE PATH "output dir for built executables")
 	set(LIBRARY_OUTPUT_PATH ${PROJECT_BINARY_DIR}/lib CACHE PATH "output dir for built libraries")
 	add_definitions(-DDEFAULT_TARGET_TRIPLE=\\"${DEFAULT_TARGET}\\")
+    add_definitions(-DDEFAULT_ALT_TARGET_TRIPLE=\\"${DEFAULT_ALT_TARGET}\\")
 else(CMAKE_MINOR_VERSION LESS 6)
 	add_definitions(-DDEFAULT_TARGET_TRIPLE="${DEFAULT_TARGET}")
+    add_definitions(-DDEFAULT_ALT_TARGET_TRIPLE="${DEFAULT_ALT_TARGET}")
 endif(CMAKE_MINOR_VERSION LESS 6)
 
 add_executable(${LDC_EXE} ${LDC_SOURCE_FILES})
diff --git a/gen/cl_options.cpp b/gen/cl_options.cpp
index bb8963c9..c8870328 100644
--- a/gen/cl_options.cpp
+++ b/gen/cl_options.cpp
@@ -225,10 +225,13 @@ cl::opt<const llvm::TargetMachineRegistry::entry*, false,
         llvm::RegistryParser<llvm::TargetMachine> > mArch("march",
     cl::desc("Architecture to generate code for:"));
 
-static cl::alias m("m",
-    cl::desc("Alias for '-march' for backwards compatibility"),
-    cl::Prefix,
-    cl::aliasopt(mArch));
+cl::opt<bool> m32bits("m32",
+    cl::desc("32 bit target"),
+    cl::ZeroOrMore);
+
+cl::opt<bool> m64bits("m64",
+    cl::desc("64 bit target"),
+    cl::ZeroOrMore);
 
 cl::opt<std::string> mCPU("mcpu",
     cl::desc("Target a specific cpu type (-mcpu=help for details)"),
diff --git a/gen/cl_options.h b/gen/cl_options.h
index 311fe13b..32dcbeb0 100644
--- a/gen/cl_options.h
+++ b/gen/cl_options.h
@@ -38,6 +38,8 @@ namespace opts {
 
     extern cl::opt<const llvm::TargetMachineRegistry::entry*, false,
                     llvm::RegistryParser<llvm::TargetMachine> > mArch;
+    extern cl::opt<bool> m32bits;
+    extern cl::opt<bool> m64bits;
     extern cl::opt<std::string> mCPU;
     extern cl::list<std::string> mAttrs;
     extern cl::opt<std::string> mTargetTriple;
diff --git a/gen/main.cpp b/gen/main.cpp
index 9023e5a3..dbdc4c9e 100644
--- a/gen/main.cpp
+++ b/gen/main.cpp
@@ -337,8 +337,24 @@ int main(int argc, char** argv)
     }
 
     // create a proper target
+
+    // check -m32/64 sanity
+    if (m32bits && m64bits)
+        error("cannot use both -m32 and -m64 options");
+    else if ((m32bits || m64bits) && (mArch != 0 || !mTargetTriple.empty()))
+        error("-m32 and -m64 switches cannot be used together with -march and -mtriple switches");
+    if (global.errors)
+        fatal();
+
     llvm::Module mod("dummy");
 
+    // override triple if needed
+    const char* defaultTriple = DEFAULT_TARGET_TRIPLE;
+    if ((sizeof(void*) == 4 && m64bits) || (sizeof(void*) == 8 && m32bits))
+    {
+        defaultTriple = DEFAULT_ALT_TARGET_TRIPLE;
+    }
+
     // did the user override the target triple?
     if (mTargetTriple.empty())
     {
@@ -347,7 +363,7 @@ int main(int argc, char** argv)
             error("you must specify a target triple as well with -mtriple when using the -march option");
             fatal();
         }
-        global.params.targetTriple = DEFAULT_TARGET_TRIPLE;
+        global.params.targetTriple = defaultTriple;
     }
     else
     {