r600g: use a select to handle front/back color in llvm

Reviewed-by: Tom Stellard <thomas.stellard@amd.com>

diff --git a/src/gallium/drivers/r600/r600_llvm.c b/src/gallium/drivers/r600/r600_llvm.c
index 71ea57812204384fecf0fabbd6c5a948e20bc7c8..c6e60afaba3fd93e8ae02c9c3426065bbb90b187 100644 (file)
--- a/src/gallium/drivers/r600/r600_llvm.c
+++ b/src/gallium/drivers/r600/r600_llvm.c
@@ -86,6 +86,42 @@ static void llvm_load_input(
                                "llvm.R600.load.input",
                                ctx->soa.bld_base.base.elem_type, &reg, 1,
                                LLVMReadNoneAttribute);
+                               
+               if (decl->Semantic.Name == TGSI_SEMANTIC_COLOR && ctx->two_side) {
+                       unsigned back_reg = ctx->r600_inputs[input_index]
+                               .potential_back_facing_reg;
+                       unsigned back_soa_index = radeon_llvm_reg_index_soa(
+                               ctx->r600_inputs[back_reg].gpr
+                               , chan);
+                       LLVMValueRef backcolor_reg = lp_build_const_int32(
+                               ctx->soa.bld_base.base.gallivm,
+                               back_soa_index);
+                       LLVMValueRef backcolor = build_intrinsic(
+                               ctx->soa.bld_base.base.gallivm->builder,
+                               "llvm.R600.load.input",
+                               ctx->soa.bld_base.base.elem_type, &backcolor_reg, 1,
+                               LLVMReadNoneAttribute);
+                       LLVMValueRef face_reg = lp_build_const_int32(
+                               ctx->soa.bld_base.base.gallivm,
+                               ctx->face_input * 4);
+                       LLVMValueRef face = build_intrinsic(
+                               ctx->soa.bld_base.base.gallivm->builder,
+                               "llvm.R600.load.input",
+                               ctx->soa.bld_base.base.elem_type,
+                               &face_reg, 1,
+                               LLVMReadNoneAttribute);
+                       LLVMValueRef is_face_positive = LLVMBuildFCmp(
+                               ctx->soa.bld_base.base.gallivm->builder,
+                               LLVMRealUGT, face, 
+                               lp_build_const_float(ctx->soa.bld_base.base.gallivm, 0.0f),
+                               "");
+                       ctx->inputs[soa_index] = LLVMBuildSelect(
+                               ctx->soa.bld_base.base.gallivm->builder,
+                               is_face_positive,
+                               ctx->inputs[soa_index],
+                               backcolor,
+                               "");
+               }
        }
 }
 

diff --git a/src/gallium/drivers/r600/r600_shader.c b/src/gallium/drivers/r600/r600_shader.c
index 0c585de8263ca9a1a63bf8e92458b85e0f11b0d2..daa508234486caf462543287d47efc29c937251f 100644 (file)
--- a/src/gallium/drivers/r600/r600_shader.c
+++ b/src/gallium/drivers/r600/r600_shader.c
@@ -1128,7 +1128,7 @@ static int tgsi_split_literal_constant(struct r600_shader_ctx *ctx)
        return 0;
 }
 
-static int process_twoside_color_inputs(struct r600_shader_ctx *ctx)
+static int process_twoside_color_inputs(struct r600_shader_ctx *ctx, unsigned use_llvm)
 {
        int i, r, count = ctx->shader->ninput;
 
@@ -1139,9 +1139,12 @@ static int process_twoside_color_inputs(struct r600_shader_ctx *ctx)
                                if ((r = evergreen_interp_input(ctx, back_facing_reg)))
                                        return r;
                        }
-                       r = select_twoside_color(ctx, i, back_facing_reg);
-                       if (r)
-                               return r;
+                       
+                       if (!use_llvm) {
+                               r = select_twoside_color(ctx, i, back_facing_reg);
+                               if (r)
+                                       return r;
+                       }
                }
        }
        return 0;
@@ -1402,7 +1405,7 @@ static int r600_shader_from_tgsi(struct r600_screen *rscreen,
        }
 
        if (shader->two_side && ctx.colors_used) {
-               if ((r = process_twoside_color_inputs(&ctx)))
+               if ((r = process_twoside_color_inputs(&ctx, use_llvm)))
                        return r;
        }