[Mesa-dev] [PATCH 1/2] gallivm: add no-signed-zeros-fp-math option to lp_create_builder

[Brian Paul]

On 01/30/2017 11:44 AM, Marek Olšák wrote:
> From: Marek Olšák <marek.olsak at amd.com>
>
> ---
>   src/gallium/auxiliary/gallivm/lp_bld_misc.cpp       | 15 ++++++++++++---
>   src/gallium/auxiliary/gallivm/lp_bld_misc.h         |  8 +++++++-
>   src/gallium/drivers/radeonsi/si_shader_tgsi_setup.c |  6 +++++-
>   3 files changed, 24 insertions(+), 5 deletions(-)
>
> diff --git a/src/gallium/auxiliary/gallivm/lp_bld_misc.cpp b/src/gallium/auxiliary/gallivm/lp_bld_misc.cpp
> index 498bbd7..3063a3c 100644
> --- a/src/gallium/auxiliary/gallivm/lp_bld_misc.cpp
> +++ b/src/gallium/auxiliary/gallivm/lp_bld_misc.cpp
> @@ -735,24 +735,33 @@ extern "C" bool
>   lp_is_function(LLVMValueRef v)
>   {
>   #if HAVE_LLVM >= 0x0309
>   	return LLVMGetValueKind(v) == LLVMFunctionValueKind;
>   #else
>   	return llvm::isa<llvm::Function>(llvm::unwrap(v));
>   #endif
>   }
>
>   extern "C" LLVMBuilderRef
> -lp_create_builder(LLVMContextRef ctx, bool unsafe_fpmath)
> +lp_create_builder(LLVMContextRef ctx, enum lp_builder_type type)
>   {
>      LLVMBuilderRef builder = LLVMCreateBuilderInContext(ctx);
>
>   #if HAVE_LLVM >= 0x0308
> -   if (unsafe_fpmath) {
> -      llvm::FastMathFlags flags;
> +   llvm::FastMathFlags flags;
> +
> +   switch (type) {
> +   case LP_BUILDER_DEFAULT:
> +      break;
> +   case LP_BUILDER_NO_SIGNED_ZEROS_FP_MATH:
> +      flags.setNoSignedZeros();
> +      llvm::unwrap(builder)->setFastMathFlags(flags);
> +      break;
> +   case LP_BUILDER_UNSAFE_FP_MATH:
>         flags.setUnsafeAlgebra();
>         llvm::unwrap(builder)->setFastMathFlags(flags);
> +      break;
>      }
>   #endif
>
>      return builder;
>   }
> diff --git a/src/gallium/auxiliary/gallivm/lp_bld_misc.h b/src/gallium/auxiliary/gallivm/lp_bld_misc.h
> index c499a6f..736a916 100644
> --- a/src/gallium/auxiliary/gallivm/lp_bld_misc.h
> +++ b/src/gallium/auxiliary/gallivm/lp_bld_misc.h
> @@ -75,19 +75,25 @@ lp_free_memory_manager(LLVMMCJITMemoryManagerRef memorymgr);
>
>   extern void
>   lp_add_attr_dereferenceable(LLVMValueRef val, uint64_t bytes);
>
>   extern LLVMValueRef
>   lp_get_called_value(LLVMValueRef call);
>
>   extern bool
>   lp_is_function(LLVMValueRef v);
>
> +enum lp_builder_type {
> +   LP_BUILDER_DEFAULT,
> +   LP_BUILDER_NO_SIGNED_ZEROS_FP_MATH,
> +   LP_BUILDER_UNSAFE_FP_MATH,
> +};

lp_builder_type seems a little generic.  How about something like 
lp_float_behavior?

-Brian


> +
>   extern LLVMBuilderRef
> -lp_create_builder(LLVMContextRef ctx, bool unsafe_fpmath);
> +lp_create_builder(LLVMContextRef ctx, enum lp_builder_type type);
>
>   #ifdef __cplusplus
>   }
>   #endif
>
>
>   #endif /* !LP_BLD_MISC_H */
> diff --git a/src/gallium/drivers/radeonsi/si_shader_tgsi_setup.c b/src/gallium/drivers/radeonsi/si_shader_tgsi_setup.c
> index 4f355e5..68153af 100644
> --- a/src/gallium/drivers/radeonsi/si_shader_tgsi_setup.c
> +++ b/src/gallium/drivers/radeonsi/si_shader_tgsi_setup.c
> @@ -1267,22 +1267,26 @@ void si_llvm_context_init(struct si_shader_context *ctx,
>   	ctx->screen = sscreen;
>   	ctx->tm = tm;
>   	ctx->type = info ? info->processor : -1;
>
>   	ctx->gallivm.context = LLVMContextCreate();
>   	ctx->gallivm.module = LLVMModuleCreateWithNameInContext("tgsi",
>   						ctx->gallivm.context);
>   	LLVMSetTarget(ctx->gallivm.module, "amdgcn--");
>
>   	bool unsafe_fpmath = (sscreen->b.debug_flags & DBG_UNSAFE_MATH) != 0;
> +	enum lp_builder_type builder_type =
> +		unsafe_fpmath ? LP_BUILDER_UNSAFE_FP_MATH :
> +				LP_BUILDER_DEFAULT;
> +
>   	ctx->gallivm.builder = lp_create_builder(ctx->gallivm.context,
> -						 unsafe_fpmath);
> +						 builder_type);
>
>   	ac_llvm_context_init(&ctx->ac, ctx->gallivm.context);
>   	ctx->ac.module = ctx->gallivm.module;
>   	ctx->ac.builder = ctx->gallivm.builder;
>
>   	struct lp_build_tgsi_context *bld_base = &ctx->bld_base;
>
>   	bld_base->info = info;
>
>   	if (info && info->array_max[TGSI_FILE_TEMPORARY] > 0) {
>