rust/src/rustllvm/ExecutionEngineWrapper.cpp
bors aa00f2e972 Auto merge of #26025 - alexcrichton:update-llvm, r=brson
This commit updates the LLVM submodule in use to the current HEAD of the LLVM
repository. This is primarily being done to start picking up unwinding support
for MSVC, which is currently unimplemented in the revision of LLVM we are using.
Along the way a few changes had to be made:

* As usual, lots of C++ debuginfo bindings in LLVM changed, so there were some
  significant changes to our RustWrapper.cpp
* As usual, some pass management changed in LLVM, so clang was re-scrutinized to
  ensure that we're doing the same thing as clang.
* Some optimization options are now passed directly into the
  `PassManagerBuilder` instead of through CLI switches to LLVM.
* The `NoFramePointerElim` option was removed from LLVM, favoring instead the
  `no-frame-pointer-elim` function attribute instead.
* The `LoopVectorize` option of the LLVM optimization passes has been disabled
  as it causes a divide-by-zero exception to happen in LLVM for zero-sized
  types. This is reported as https://llvm.org/bugs/show_bug.cgi?id=23763

Additionally, LLVM has picked up some new optimizations which required fixing an
existing soundness hole in the IR we generate. It appears that the current LLVM
we use does not expose this hole. When an enum is moved, the previous slot in
memory is overwritten with a bit pattern corresponding to "dropped". When the
drop glue for this slot is run, however, the switch on the discriminant can
often start executing the `unreachable` block of the switch due to the
discriminant now being outside the normal range. This was patched over locally
for now by having the `unreachable` block just change to a `ret void`.
2015-06-17 06:56:15 +00:00

133 lines
3.7 KiB
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// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
#include "rustllvm.h"
#include "llvm/ExecutionEngine/SectionMemoryManager.h"
using namespace llvm;
using namespace llvm::sys;
using namespace llvm::object;
// libmorestack is not used on other platforms
#if defined(__linux__) || defined(__APPLE__)
extern "C" void __morestack(void);
static void* morestack_addr() {
return reinterpret_cast<void*>(__morestack);
}
#endif
class RustJITMemoryManager : public SectionMemoryManager
{
typedef SectionMemoryManager Base;
public:
RustJITMemoryManager() {}
uint64_t getSymbolAddress(const std::string &Name) override
{
#if defined(__linux__) || defined(__APPLE__)
if (Name == "__morestack" || Name == "___morestack")
return reinterpret_cast<uint64_t>(__morestack);
if (Name == "__morestack_addr" || Name == "___morestack_addr")
return reinterpret_cast<uint64_t>(morestack_addr);
#endif
return Base::getSymbolAddress(Name);
}
};
DEFINE_SIMPLE_CONVERSION_FUNCTIONS(RustJITMemoryManager, LLVMRustJITMemoryManagerRef)
extern "C" LLVMBool LLVMRustLoadDynamicLibrary(const char *path)
{
std::string err;
DynamicLibrary lib = DynamicLibrary::getPermanentLibrary(path, &err);
if (!lib.isValid())
LLVMRustSetLastError(err.c_str());
return lib.isValid();
}
// Calls LLVMAddModule;
// exists for consistency with LLVMExecutionEngineRemoveModule
extern "C" void LLVMExecutionEngineAddModule(
LLVMExecutionEngineRef eeref, LLVMModuleRef mref)
{
#ifdef _WIN32
// On Windows, MCJIT must generate ELF objects
std::string target = getProcessTriple();
target += "-elf";
target = Triple::normalize(target);
unwrap(mref)->setTargetTriple(target);
#endif
LLVMAddModule(eeref, mref);
}
// LLVMRemoveModule exists in LLVM's C bindings,
// but it requires pointless parameters
extern "C" LLVMBool LLVMExecutionEngineRemoveModule(
LLVMExecutionEngineRef eeref, LLVMModuleRef mref)
{
ExecutionEngine *ee = unwrap(eeref);
Module *m = unwrap(mref);
return ee->removeModule(m);
}
extern "C" LLVMExecutionEngineRef LLVMBuildExecutionEngine(LLVMModuleRef mod)
{
// These are necessary for code generation to work properly.
InitializeNativeTarget();
InitializeNativeTargetAsmPrinter();
InitializeNativeTargetAsmParser();
#ifdef _WIN32
// On Windows, MCJIT must generate ELF objects
std::string target = getProcessTriple();
target += "-elf";
target = Triple::normalize(target);
unwrap(mod)->setTargetTriple(target);
#endif
std::string error_str;
TargetOptions options;
RustJITMemoryManager *mm = new RustJITMemoryManager;
ExecutionEngine *ee =
#if LLVM_VERSION_MINOR >= 6
EngineBuilder(std::unique_ptr<Module>(unwrap(mod)))
.setMCJITMemoryManager(std::unique_ptr<RustJITMemoryManager>(mm))
#else
EngineBuilder(unwrap(mod))
.setMCJITMemoryManager(mm)
#endif
.setEngineKind(EngineKind::JIT)
.setErrorStr(&error_str)
.setTargetOptions(options)
.create();
if (!ee)
LLVMRustSetLastError(error_str.c_str());
return wrap(ee);
}
extern "C" void LLVMExecutionEngineFinalizeObject(LLVMExecutionEngineRef eeref)
{
ExecutionEngine *ee = unwrap(eeref);
ee->finalizeObject();
}