[Mesa-dev] [PATCH] radeonsi: add a debug flag for unsafe math LLVM optimizations

[Marek Olšák]

Ping

On Mon, Jun 13, 2016 at 6:27 PM, Marek Olšák <maraeo at gmail.com> wrote:
> From: Marek Olšák <marek.olsak at amd.com>
>
> ---
>  src/gallium/drivers/radeon/r600_pipe_common.c |  1 +
>  src/gallium/drivers/radeon/r600_pipe_common.h |  1 +
>  src/gallium/drivers/radeonsi/si_shader.c      | 16 ++++++++++++++++
>  3 files changed, 18 insertions(+)
>
> diff --git a/src/gallium/drivers/radeon/r600_pipe_common.c b/src/gallium/drivers/radeon/r600_pipe_common.c
> index fa9f70d..5d4a679 100644
> --- a/src/gallium/drivers/radeon/r600_pipe_common.c
> +++ b/src/gallium/drivers/radeon/r600_pipe_common.c
> @@ -482,6 +482,7 @@ static const struct debug_named_value common_debug_options[] = {
>         { "sisched", DBG_SI_SCHED, "Enable LLVM SI Machine Instruction Scheduler." },
>         { "mono", DBG_MONOLITHIC_SHADERS, "Use old-style monolithic shaders compiled on demand" },
>         { "noce", DBG_NO_CE, "Disable the constant engine"},
> +       { "unsafemath", DBG_UNSAFE_MATH, "Enable unsafe math shader optimizations" },
>
>         DEBUG_NAMED_VALUE_END /* must be last */
>  };
> diff --git a/src/gallium/drivers/radeon/r600_pipe_common.h b/src/gallium/drivers/radeon/r600_pipe_common.h
> index 77dfc4f..263ef5e 100644
> --- a/src/gallium/drivers/radeon/r600_pipe_common.h
> +++ b/src/gallium/drivers/radeon/r600_pipe_common.h
> @@ -99,6 +99,7 @@
>  #define DBG_SI_SCHED           (1llu << 46)
>  #define DBG_MONOLITHIC_SHADERS (1llu << 47)
>  #define DBG_NO_CE              (1llu << 48)
> +#define DBG_UNSAFE_MATH                (1llu << 49)
>
>  #define R600_MAP_BUFFER_ALIGNMENT 64
>  #define R600_MAX_VIEWPORTS        16
> diff --git a/src/gallium/drivers/radeonsi/si_shader.c b/src/gallium/drivers/radeonsi/si_shader.c
> index 6dc4985..bba6a55 100644
> --- a/src/gallium/drivers/radeonsi/si_shader.c
> +++ b/src/gallium/drivers/radeonsi/si_shader.c
> @@ -5255,6 +5255,22 @@ static void si_create_function(struct si_shader_context *ctx,
>                 else
>                         LLVMAddAttribute(P, LLVMInRegAttribute);
>         }
> +
> +       if (ctx->screen->b.debug_flags & DBG_UNSAFE_MATH) {
> +               /* These were copied from some LLVM test. */
> +               LLVMAddTargetDependentFunctionAttr(ctx->radeon_bld.main_fn,
> +                                                  "less-precise-fpmad",
> +                                                  "true");
> +               LLVMAddTargetDependentFunctionAttr(ctx->radeon_bld.main_fn,
> +                                                  "no-infs-fp-math",
> +                                                  "true");
> +               LLVMAddTargetDependentFunctionAttr(ctx->radeon_bld.main_fn,
> +                                                  "no-nans-fp-math",
> +                                                  "true");
> +               LLVMAddTargetDependentFunctionAttr(ctx->radeon_bld.main_fn,
> +                                                  "unsafe-fp-math",
> +                                                  "true");
> +       }
>  }
>
>  static void create_meta_data(struct si_shader_context *ctx)
> --
> 2.7.4
>