radeonsi: compute how many input SGPRs and VGPRs shaders have

Prologs (shader binaries inserted before the API shader binary) need to
know this, so that they won't change the input registers unintentionally.

Reviewed-by: Nicolai Hähnle <[email protected]>

2 files changed, 34 insertions, 0 deletions

diff --git a/src/gallium/drivers/radeonsi/si_shader.c b/src/gallium/drivers/radeonsi/si_shader.c
index 422608eb4ce..1145f896a39 100644
--- a/src/gallium/drivers/radeonsi/si_shader.c
+++ b/src/gallium/drivers/radeonsi/si_shader.c
@@ -3580,6 +3580,26 @@ static void declare_streamout_params(struct si_shader_context *ctx,
 	}
 }
 
+static unsigned llvm_get_type_size(LLVMTypeRef type)
+{
+	LLVMTypeKind kind = LLVMGetTypeKind(type);
+
+	switch (kind) {
+	case LLVMIntegerTypeKind:
+		return LLVMGetIntTypeWidth(type) / 8;
+	case LLVMFloatTypeKind:
+		return 4;
+	case LLVMPointerTypeKind:
+		return 8;
+	case LLVMVectorTypeKind:
+		return LLVMGetVectorSize(type) *
+		       llvm_get_type_size(LLVMGetElementType(type));
+	default:
+		assert(0);
+		return 0;
+	}
+}
+
 static void create_function(struct si_shader_context *ctx)
 {
 	struct lp_build_tgsi_context *bld_base = &ctx->radeon_bld.soa.bld_base;
@@ -3717,6 +3737,9 @@ static void create_function(struct si_shader_context *ctx)
 	radeon_llvm_shader_type(ctx->radeon_bld.main_fn, ctx->type);
 	ctx->return_value = LLVMGetUndef(ctx->radeon_bld.return_type);
 
+	shader->num_input_sgprs = 0;
+	shader->num_input_vgprs = 0;
+
 	for (i = 0; i <= last_sgpr; ++i) {
 		LLVMValueRef P = LLVMGetParam(ctx->radeon_bld.main_fn, i);
 
@@ -3726,8 +3749,17 @@ static void create_function(struct si_shader_context *ctx)
 			LLVMAddAttribute(P, LLVMByValAttribute);
 		else
 			LLVMAddAttribute(P, LLVMInRegAttribute);
+
+		shader->num_input_sgprs += llvm_get_type_size(params[i]) / 4;
 	}
 
+	/* Unused fragment shader inputs are eliminated by the compiler,
+	 * so we don't know yet how many there will be.
+	 */
+	if (ctx->type != TGSI_PROCESSOR_FRAGMENT)
+		for (; i < num_params; ++i)
+			shader->num_input_vgprs += llvm_get_type_size(params[i]) / 4;
+
 	if (bld_base->info &&
 	    (bld_base->info->opcode_count[TGSI_OPCODE_DDX] > 0 ||
 	     bld_base->info->opcode_count[TGSI_OPCODE_DDY] > 0 ||
diff --git a/src/gallium/drivers/radeonsi/si_shader.h b/src/gallium/drivers/radeonsi/si_shader.h
index dc75e0330e4..131455b6d0f 100644
--- a/src/gallium/drivers/radeonsi/si_shader.h
+++ b/src/gallium/drivers/radeonsi/si_shader.h
@@ -279,6 +279,8 @@ struct si_shader {
 	struct radeon_shader_binary	binary;
 	struct si_shader_config		config;
 
+	ubyte			num_input_sgprs;
+	ubyte			num_input_vgprs;
 	unsigned		vs_output_param_offset[PIPE_MAX_SHADER_OUTPUTS];
 	bool			uses_instanceid;
 	unsigned		nr_pos_exports;