gallivm: Support MCJIT on Windows.

It works fine, though it requires using ELF objects.

With this change there is nothing preventing us to switch exclusively
to MCJIT, everywhere.  It's still off though.

2 files changed, 12 insertions, 5 deletions

diff --git a/scons/llvm.py b/scons/llvm.py
index cdfbe43..288a080 100644
--- a/scons/llvm.py
+++ b/scons/llvm.py
@@ -104,7 +104,7 @@ def generate(env):
                 'LLVMBitWriter', 'LLVMX86Disassembler', 'LLVMX86AsmParser',
                 'LLVMX86CodeGen', 'LLVMX86Desc', 'LLVMSelectionDAG',
                 'LLVMAsmPrinter', 'LLVMMCParser', 'LLVMX86AsmPrinter',
-                'LLVMX86Utils', 'LLVMX86Info', 'LLVMJIT',
+                'LLVMX86Utils', 'LLVMX86Info', 'LLVMMCJIT', 'LLVMJIT',
                 'LLVMExecutionEngine', 'LLVMCodeGen', 'LLVMScalarOpts',
                 'LLVMInstCombine', 'LLVMTransformUtils', 'LLVMipa',
                 'LLVMAnalysis', 'LLVMTarget', 'LLVMMC', 'LLVMCore',
@@ -116,7 +116,7 @@ def generate(env):
                 'LLVMBitWriter', 'LLVMX86Disassembler', 'LLVMX86AsmParser',
                 'LLVMX86CodeGen', 'LLVMX86Desc', 'LLVMSelectionDAG',
                 'LLVMAsmPrinter', 'LLVMMCParser', 'LLVMX86AsmPrinter',
-                'LLVMX86Utils', 'LLVMX86Info', 'LLVMJIT',
+                'LLVMX86Utils', 'LLVMX86Info', 'LLVMMCJIT', 'LLVMJIT',
                 'LLVMExecutionEngine', 'LLVMCodeGen', 'LLVMScalarOpts',
                 'LLVMInstCombine', 'LLVMTransformUtils', 'LLVMipa',
                 'LLVMAnalysis', 'LLVMTarget', 'LLVMMC', 'LLVMCore',
@@ -165,9 +165,7 @@ def generate(env):
             if '-fno-rtti' in cxxflags:
                 env.Append(CXXFLAGS = ['-fno-rtti'])
 
-            components = ['engine', 'bitwriter', 'x86asmprinter']
-
-            components.append('mcjit')
+            components = ['engine', 'mcjit', 'bitwriter', 'x86asmprinter']
 
             env.ParseConfig('llvm-config --libs ' + ' '.join(components))
             env.ParseConfig('llvm-config --ldflags')
diff --git a/src/gallium/auxiliary/gallivm/lp_bld_misc.cpp b/src/gallium/auxiliary/gallivm/lp_bld_misc.cpp
index d03680f..d1cc9b6 100644
--- a/src/gallium/auxiliary/gallivm/lp_bld_misc.cpp
+++ b/src/gallium/auxiliary/gallivm/lp_bld_misc.cpp
@@ -57,6 +57,7 @@
 #include <llvm/ADT/Triple.h>
 #include <llvm/ExecutionEngine/JITMemoryManager.h>
 #include <llvm/Support/CommandLine.h>
+#include <llvm/Support/Host.h>
 #include <llvm/Support/PrettyStackTrace.h>
 
 #include <llvm/Support/TargetSelect.h>
@@ -452,6 +453,14 @@ lp_build_create_jit_compiler_for_module(LLVMExecutionEngineRef *OutJIT,
 
    if (useMCJIT) {
        builder.setUseMCJIT(true);
+#ifdef _WIN32
+       /*
+        * MCJIT works on Windows, but currently only through ELF object format.
+        */
+       std::string targetTriple = llvm::sys::getProcessTriple();
+       targetTriple.append("-elf");
+       unwrap(M)->setTargetTriple(targetTriple);
+#endif
    }
 
    llvm::SmallVector<std::string, 1> MAttrs;