[Mesa-dev] [PATCH] gallivm: fix indirect src register fetches requiring bitcast

[Jose Fonseca]

Good catch Roland.

Reviewed-by: Jose Fonseca <jfonseca at vmware.com>

Jose

----- Original Message -----
> From: Roland Scheidegger <sroland at vmware.com>
> 
> For constant and temporary register fetches, the bitcasts weren't done
> correctly for the indirect case, leading to crashes due to type mismatches.
> Simply do the bitcasts after fetching (much simpler than fixing up the load
> pointer for the various cases).
> 
> This fixes https://bugs.freedesktop.org/show_bug.cgi?id=61036
> ---
>  src/gallium/auxiliary/gallivm/lp_bld_tgsi_soa.c |   37
>  ++++++++++-------------
>  1 file changed, 16 insertions(+), 21 deletions(-)
> 
> diff --git a/src/gallium/auxiliary/gallivm/lp_bld_tgsi_soa.c
> b/src/gallium/auxiliary/gallivm/lp_bld_tgsi_soa.c
> index ae4a577..69957fe 100644
> --- a/src/gallium/auxiliary/gallivm/lp_bld_tgsi_soa.c
> +++ b/src/gallium/auxiliary/gallivm/lp_bld_tgsi_soa.c
> @@ -603,10 +603,10 @@ emit_fetch_constant(
>     LLVMBuilderRef builder = gallivm->builder;
>     struct lp_build_context *uint_bld = &bld_base->uint_bld;
>     LLVMValueRef indirect_index = NULL;
> -   struct lp_build_context *bld_fetch = stype_to_fetch(bld_base, stype);
>     unsigned dimension = 0;
>     LLVMValueRef dimension_index;
>     LLVMValueRef consts_ptr;
> +   LLVMValueRef res;
>  
>     /* XXX: Handle fetching xyzw components as a vector */
>     assert(swizzle != ~0);
> @@ -637,7 +637,7 @@ emit_fetch_constant(
>        index_vec = lp_build_add(uint_bld, index_vec, swizzle_vec);
>  
>        /* Gather values from the constant buffer */
> -      return build_gather(bld_fetch, consts_ptr, index_vec);
> +      res = build_gather(&bld_base->base, consts_ptr, index_vec);
>     }
>     else {
>        LLVMValueRef index;  /* index into the const buffer */
> @@ -646,18 +646,16 @@ emit_fetch_constant(
>        index = lp_build_const_int32(gallivm, reg->Register.Index*4 +
>        swizzle);
>  
>        scalar_ptr = LLVMBuildGEP(builder, consts_ptr,
> -                                   &index, 1, "");
> -
> -      if (stype != TGSI_TYPE_FLOAT && stype != TGSI_TYPE_UNTYPED) {
> -         LLVMTypeRef ivtype =
> LLVMPointerType(LLVMInt32TypeInContext(gallivm->context), 0);
> -         LLVMValueRef temp_ptr;
> -         temp_ptr = LLVMBuildBitCast(builder, scalar_ptr, ivtype, "");
> -         scalar = LLVMBuildLoad(builder, temp_ptr, "");
> -      } else
> -         scalar = LLVMBuildLoad(builder, scalar_ptr, "");
> +                                &index, 1, "");
> +      scalar = LLVMBuildLoad(builder, scalar_ptr, "");
> +      res = lp_build_broadcast_scalar(&bld_base->base, scalar);
> +   }
>  
> -      return lp_build_broadcast_scalar(bld_fetch, scalar);
> +   if (stype == TGSI_TYPE_SIGNED || stype == TGSI_TYPE_UNSIGNED) {
> +      struct lp_build_context *bld_fetch = stype_to_fetch(bld_base, stype);
> +      res = LLVMBuildBitCast(builder, res, bld_fetch->vec_type, "");
>     }
> +   return res;
>  }
>  
>  static LLVMValueRef
> @@ -791,16 +789,13 @@ emit_fetch_temporary(
>     }
>     else {
>        LLVMValueRef temp_ptr;
> -      if (stype != TGSI_TYPE_FLOAT && stype != TGSI_TYPE_UNTYPED) {
> -         LLVMTypeRef itype = LLVMPointerType(bld->bld_base.int_bld.vec_type,
> 0);
> -         LLVMValueRef tint_ptr = lp_get_temp_ptr_soa(bld,
> reg->Register.Index,
> -                                                     swizzle);
> -         temp_ptr = LLVMBuildBitCast(builder, tint_ptr, itype, "");
> -      } else
> -         temp_ptr = lp_get_temp_ptr_soa(bld, reg->Register.Index, swizzle);
> +      temp_ptr = lp_get_temp_ptr_soa(bld, reg->Register.Index, swizzle);
>        res = LLVMBuildLoad(builder, temp_ptr, "");
> -      if (!res)
> -         return bld->bld_base.base.undef;
> +   }
> +
> +   if (stype == TGSI_TYPE_SIGNED || stype == TGSI_TYPE_UNSIGNED) {
> +      struct lp_build_context *bld_fetch = stype_to_fetch(bld_base, stype);
> +      res = LLVMBuildBitCast(builder, res, bld_fetch->vec_type, "");
>     }
>  
>     return res;
> --
> 1.7.9.5
>