radeonsi: load the streamout buf descriptors closer to their use
LLVM can still decide to hoist the loads since they're marked invariant.
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
diff --git a/src/gallium/drivers/radeonsi/si_shader.c b/src/gallium/drivers/radeonsi/si_shader.c
index 576363e..601085d 100644
--- a/src/gallium/drivers/radeonsi/si_shader.c
+++ b/src/gallium/drivers/radeonsi/si_shader.c
@@ -2274,19 +2274,6 @@
LLVMBuilderRef builder = gallivm->builder;
int i;
struct lp_build_if_state if_ctx;
- LLVMValueRef so_buffers[4];
- LLVMValueRef buf_ptr = LLVMGetParam(ctx->main_fn,
- SI_PARAM_RW_BUFFERS);
-
- /* Load the descriptors. */
- for (i = 0; i < 4; ++i) {
- if (ctx->shader->selector->so.stride[i]) {
- LLVMValueRef offset = lp_build_const_int32(gallivm,
- SI_VS_STREAMOUT_BUF0 + i);
-
- so_buffers[i] = build_indexed_load_const(ctx, buf_ptr, offset);
- }
- }
/* Get bits [22:16], i.e. (so_param >> 16) & 127; */
LLVMValueRef so_vtx_count =
@@ -2319,12 +2306,22 @@
/* Compute (streamout_write_index + thread_id). */
so_write_index = LLVMBuildAdd(builder, so_write_index, tid, "");
- /* Compute the write offset for each enabled buffer. */
+ /* Load the descriptor and compute the write offset for each
+ * enabled buffer. */
LLVMValueRef so_write_offset[4] = {};
+ LLVMValueRef so_buffers[4];
+ LLVMValueRef buf_ptr = LLVMGetParam(ctx->main_fn,
+ SI_PARAM_RW_BUFFERS);
+
for (i = 0; i < 4; i++) {
if (!so->stride[i])
continue;
+ LLVMValueRef offset = lp_build_const_int32(gallivm,
+ SI_VS_STREAMOUT_BUF0 + i);
+
+ so_buffers[i] = build_indexed_load_const(ctx, buf_ptr, offset);
+
LLVMValueRef so_offset = LLVMGetParam(ctx->main_fn,
ctx->param_streamout_offset[i]);
so_offset = LLVMBuildMul(builder, so_offset, LLVMConstInt(ctx->i32, 4, 0), "");
