Mesa (master): ac/nir: Don't load the descriptor in vulkan_resource_index.

[Bas Nieuwenhuizen]

Module: Mesa
Branch: master
Commit: 368f49b284d6ad4567d0baf718de499ce8decf00
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=368f49b284d6ad4567d0baf718de499ce8decf00

Author: Bas Nieuwenhuizen <bas at basnieuwenhuizen.nl>
Date:   Sun Dec 10 23:18:32 2017 +0100

ac/nir: Don't load the descriptor in vulkan_resource_index.

To support the reindex intrinsic, we need the result to be
something on which we can adjust the index/address.

Since it is all within a basic block, the compiler should be
able to merge any extra loads.

v2: Change visit_get_buffer_size too.
Reviewed-by: Dave Airlie <airlied at redhat.com>

---

 src/amd/common/ac_nir_to_llvm.c | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/src/amd/common/ac_nir_to_llvm.c b/src/amd/common/ac_nir_to_llvm.c
index 663b27d265..2016a5d067 100644
--- a/src/amd/common/ac_nir_to_llvm.c
+++ b/src/amd/common/ac_nir_to_llvm.c
@@ -2227,7 +2227,7 @@ static LLVMValueRef visit_vulkan_resource_index(struct nir_to_llvm_context *ctx,
 	desc_ptr = cast_ptr(ctx, desc_ptr, ctx->ac.v4i32);
 	LLVMSetMetadata(desc_ptr, ctx->ac.uniform_md_kind, ctx->ac.empty_md);
 
-	return LLVMBuildLoad(ctx->builder, desc_ptr, "");
+	return desc_ptr;
 }
 
 static LLVMValueRef visit_load_push_constant(struct nir_to_llvm_context *ctx,
@@ -2247,9 +2247,9 @@ static LLVMValueRef visit_load_push_constant(struct nir_to_llvm_context *ctx,
 static LLVMValueRef visit_get_buffer_size(struct ac_nir_context *ctx,
                                           const nir_intrinsic_instr *instr)
 {
-	LLVMValueRef desc = get_src(ctx, instr->src[0]);
+	LLVMValueRef ptr = get_src(ctx, instr->src[0]);
 
-	return get_buffer_size(ctx, desc, false);
+	return get_buffer_size(ctx, LLVMBuildLoad(ctx->ac.builder, ptr, ""), false);
 }
 static void visit_store_ssbo(struct ac_nir_context *ctx,
                              nir_intrinsic_instr *instr)
@@ -4233,14 +4233,21 @@ static void visit_intrinsic(struct ac_nir_context *ctx,
 }
 
 static LLVMValueRef radv_load_ssbo(struct ac_shader_abi *abi,
-				   LLVMValueRef buffer, bool write)
+				   LLVMValueRef buffer_ptr, bool write)
 {
 	struct nir_to_llvm_context *ctx = nir_to_llvm_context_from_abi(abi);
 
 	if (write && ctx->stage == MESA_SHADER_FRAGMENT)
 		ctx->shader_info->fs.writes_memory = true;
 
-	return buffer;
+	return LLVMBuildLoad(ctx->builder, buffer_ptr, "");
+}
+
+static LLVMValueRef radv_load_ubo(struct ac_shader_abi *abi, LLVMValueRef buffer_ptr)
+{
+	struct nir_to_llvm_context *ctx = nir_to_llvm_context_from_abi(abi);
+
+	return LLVMBuildLoad(ctx->builder, buffer_ptr, "");
 }
 
 static LLVMValueRef radv_get_sampler_desc(struct ac_shader_abi *abi,
@@ -6541,6 +6548,7 @@ LLVMModuleRef ac_translate_nir_to_llvm(LLVMTargetMachineRef tm,
 	ctx.abi.inputs = &ctx.inputs[0];
 	ctx.abi.emit_outputs = handle_shader_outputs_post;
 	ctx.abi.emit_vertex = visit_emit_vertex;
+	ctx.abi.load_ubo = radv_load_ubo;
 	ctx.abi.load_ssbo = radv_load_ssbo;
 	ctx.abi.load_sampler_desc = radv_get_sampler_desc;
 	ctx.abi.clamp_shadow_reference = false;