From a93a4d259ae3670d748859f430aba94f065ea6df Mon Sep 17 00:00:00 2001 From: Josh Stone Date: Tue, 27 Mar 2018 12:27:45 -0700 Subject: [PATCH] Enable target_feature on any LLVM 6+ In `LLVMRustHasFeature()`, rather than using `MCInfo->getFeatureTable()` that is specific to Rust's LLVM fork, we can use this in LLVM 6: /// Check whether the subtarget features are enabled/disabled as per /// the provided string, ignoring all other features. bool checkFeatures(StringRef FS) const; Now rustc using external LLVM can also have `target_feature`. --- src/rustllvm/PassWrapper.cpp | 12 ++++-------- src/test/run-pass/sse2.rs | 6 +++++- 2 files changed, 9 insertions(+), 9 deletions(-) diff --git a/src/rustllvm/PassWrapper.cpp b/src/rustllvm/PassWrapper.cpp index 3d5cce81278..382ef2cc407 100644 --- a/src/rustllvm/PassWrapper.cpp +++ b/src/rustllvm/PassWrapper.cpp @@ -205,17 +205,13 @@ GEN_SUBTARGETS extern "C" bool LLVMRustHasFeature(LLVMTargetMachineRef TM, const char *Feature) { -#if LLVM_RUSTLLVM +#if LLVM_VERSION_GE(6, 0) TargetMachine *Target = unwrap(TM); const MCSubtargetInfo *MCInfo = Target->getMCSubtargetInfo(); - const FeatureBitset &Bits = MCInfo->getFeatureBits(); - const ArrayRef FeatTable = MCInfo->getFeatureTable(); - - for (auto &FeatureEntry : FeatTable) - if (!strcmp(FeatureEntry.Key, Feature)) - return (Bits & FeatureEntry.Value) == FeatureEntry.Value; -#endif + return MCInfo->checkFeatures(std::string("+") + Feature); +#else return false; +#endif } enum class LLVMRustCodeModel { diff --git a/src/test/run-pass/sse2.rs b/src/test/run-pass/sse2.rs index 22469b2fde0..b1d7e5435c4 100644 --- a/src/test/run-pass/sse2.rs +++ b/src/test/run-pass/sse2.rs @@ -8,7 +8,8 @@ // option. This file may not be copied, modified, or distributed // except according to those terms. -// no-system-llvm -- needs MCSubtargetInfo::getFeatureTable() +// min-llvm-version 6.0 +// ^ needs MCSubtargetInfo::checkFeatures() // ignore-cloudabi no std::env #![feature(cfg_target_feature)] @@ -29,4 +30,7 @@ fn main() { assert!(cfg!(target_feature = "sse2"), "SSE2 was not detected as available on an x86 platform"); } + // check a negative case too -- whitelisted on x86, but not enabled by default + assert!(cfg!(not(target_feature = "avx2")), + "AVX2 shouldn't be detected as available by default on any platform"); } -- 2.44.0