r600g/llvm: Undefines unrequired texture coord values

This is a port of "r600g:mask unused source components for SAMPLE"
patch from Vadim Girlin.

diff --git a/src/gallium/drivers/r600/r600_llvm.c b/src/gallium/drivers/r600/r600_llvm.c
index 83d7340..2ff109c 100644 (file)
--- a/src/gallium/drivers/r600/r600_llvm.c
+++ b/src/gallium/drivers/r600/r600_llvm.c
@@ -429,9 +429,36 @@ static void llvm_emit_tex(
                }
        }
 
+       if (emit_data->inst->Instruction.Opcode == TGSI_OPCODE_TEX) {
+               LLVMValueRef Vector[4] = {
+                       LLVMBuildExtractElement(gallivm->builder, emit_data->args[0],
+                               lp_build_const_int32(gallivm, 0), ""),
+                       LLVMBuildExtractElement(gallivm->builder, emit_data->args[0],
+                               lp_build_const_int32(gallivm, 1), ""),
+                       LLVMBuildExtractElement(gallivm->builder, emit_data->args[0],
+                               lp_build_const_int32(gallivm, 2), ""),
+                       LLVMBuildExtractElement(gallivm->builder, emit_data->args[0],
+                               lp_build_const_int32(gallivm, 3), ""),
+               };
+               switch (emit_data->inst->Texture.Texture) {
+               case TGSI_TEXTURE_2D:
+               case TGSI_TEXTURE_RECT:
+                       Vector[2] = Vector[3] = LLVMGetUndef(bld_base->base.elem_type);
+                       break;
+               case TGSI_TEXTURE_1D:
+                       Vector[1] = Vector[2] = Vector[3] = LLVMGetUndef(bld_base->base.elem_type);
+                       break;
+               default:
+                       break;
+               }
+               args[0] = lp_build_gather_values(gallivm, Vector, 4);
+       } else {
+               args[0] = emit_data->args[0];
+       }
+
        assert(emit_data->arg_count + 2 <= Elements(args));
 
-       for (c = 0; c < emit_data->arg_count; ++c)
+       for (c = 1; c < emit_data->arg_count; ++c)
                args[c] = emit_data->args[c];
 
        sampler_src = emit_data->inst->Instruction.NumSrcRegs-1;