[CMake] Introduce LLVM_TARGET_TRIPLE_ENV as an option to override LLVM_DEFAULT_TARGET_TRIPLE at runtime.
No behavior is changed if LLVM_TARGET_TRIPLE_ENV is blank or undefined.
If LLVM_TARGET_TRIPLE_ENV is "TEST_TARGET_TRIPLE" and $TEST_TARGET_TRIPLE is not blank,
llvm::sys::getDefaultTargetTriple() returns $TEST_TARGET_TRIPLE.
Lit resets config.target_triple and config.environment[LLVM_TARGET_TRIPLE_ENV] to change the default target.
Without changing LLVM_DEFAULT_TARGET_TRIPLE nor rebuilding, lit can be run;
TEST_TARGET_TRIPLE=i686-pc-win32 bin/llvm-lit -sv path/to/test/
TEST_TARGET_TRIPLE=i686-pc-win32 ninja check-clang-tools
Differential Revision: https://reviews.llvm.org/D33662
llvm-svn: 305632
diff --git a/llvm/cmake/modules/AddLLVM.cmake b/llvm/cmake/modules/AddLLVM.cmake
index e011bb4..2b54bdb 100644
--- a/llvm/cmake/modules/AddLLVM.cmake
+++ b/llvm/cmake/modules/AddLLVM.cmake
@@ -1133,6 +1133,19 @@
set(LIT_SITE_CFG_IN_HEADER "## Autogenerated from ${input}\n## Do not edit!")
+ # Override config_target_triple (and the env)
+ if(LLVM_TARGET_TRIPLE_ENV)
+ # This is expanded into the heading.
+ string(CONCAT LIT_SITE_CFG_IN_HEADER "${LIT_SITE_CFG_IN_HEADER}\n\n"
+ "import os\n"
+ "target_env = \"${LLVM_TARGET_TRIPLE_ENV}\"\n"
+ "config.target_triple = config.environment[target_env] = os.environ.get(target_env, \"${TARGET_TRIPLE}\")\n"
+ )
+
+ # This is expanded to; config.target_triple = ""+config.target_triple+""
+ set(TARGET_TRIPLE "\"+config.target_triple+\"")
+ endif()
+
configure_file(${input} ${output} @ONLY)
endfunction()