[Mesa-dev] [PATCH] gallivm: use getHostCPUFeatures on x86/llvm-4.0+.

[Roland Scheidegger]

Am 05.12.2016 um 18:39 schrieb Tim Rowley:
> Use llvm provided API based on cpuid rather than our own
> manually mantained list of mattr enabling/disabling.
> ---
>  src/gallium/auxiliary/gallivm/lp_bld_misc.cpp | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
> 
> diff --git a/src/gallium/auxiliary/gallivm/lp_bld_misc.cpp b/src/gallium/auxiliary/gallivm/lp_bld_misc.cpp
> index a68428d..21d9e15 100644
> --- a/src/gallium/auxiliary/gallivm/lp_bld_misc.cpp
> +++ b/src/gallium/auxiliary/gallivm/lp_bld_misc.cpp
> @@ -542,6 +542,20 @@ lp_build_create_jit_compiler_for_module(LLVMExecutionEngineRef *OutJIT,
>     llvm::SmallVector<std::string, 16> MAttrs;
>  
>  #if defined(PIPE_ARCH_X86) || defined(PIPE_ARCH_X86_64)
> +#if HAVE_LLVM >= 0x0400
> +   /* llvm-3.7+ implements sys::getHostCPUFeatures for x86,
> +    * which allows us to enable/disable code generation based
> +    * on the results of cpuid.
> +    */
> +   llvm::StringMap<bool> features;
> +   llvm::sys::getHostCPUFeatures(features);
> +
> +   for (StringMapIterator<bool> f = features.begin();
> +        f != features.end();
> +        ++f) {
> +      MAttrs.push_back(((*f).second ? "+" : "-") + (*f).first().str());
> +   }
> +#else
>     /*
>      * We need to unset attributes because sometimes LLVM mistakenly assumes
>      * certain features are present given the processor name.
> @@ -596,6 +610,7 @@ lp_build_create_jit_compiler_for_module(LLVMExecutionEngineRef *OutJIT,
>     MAttrs.push_back("-avx512vl");
>  #endif
>  #endif
> +#endif
>  
>  #if defined(PIPE_ARCH_PPC)
>     MAttrs.push_back(util_cpu_caps.has_altivec ? "+altivec" : "-altivec");
> 

Reviewed-by: Roland Scheidegger <sroland at vmware.com>