From 528d70d0b5fd2722bc32d42d8859865081cf0730 Mon Sep 17 00:00:00 2001 From: Kenneth Graunke Date: Wed, 21 Aug 2013 16:01:45 -0700 Subject: [PATCH] i965/vs: Use a fixed set of register classes. Arrays, structures, and matrices use large VGRFs of arbitrary sizes. However, split_virtual_grfs() breaks those down into VGRFs of size 1. For reference, commit 5d90b988791e51cfb6413109271ad102fd7a304c is the analogous change to the FS backend. Signed-off-by: Kenneth Graunke Reviewed-by: Paul Berry --- .../dri/i965/brw_vec4_reg_allocate.cpp | 50 +++++-------------- 1 file changed, 13 insertions(+), 37 deletions(-) diff --git a/src/mesa/drivers/dri/i965/brw_vec4_reg_allocate.cpp b/src/mesa/drivers/dri/i965/brw_vec4_reg_allocate.cpp index 0b27383777f..ab75a170e33 100644 --- a/src/mesa/drivers/dri/i965/brw_vec4_reg_allocate.cpp +++ b/src/mesa/drivers/dri/i965/brw_vec4_reg_allocate.cpp @@ -97,11 +97,15 @@ vec4_visitor::reg_allocate_trivial() } static void -brw_alloc_reg_set_for_classes(struct brw_context *brw, - int *class_sizes, - int class_count, - int base_reg_count) +brw_alloc_reg_set(struct brw_context *brw, int base_reg_count) { + /* After running split_virtual_grfs(), almost all VGRFs will be of size 1. + * SEND-from-GRF sources cannot be split, so we also need classes for each + * potential message length. + */ + const int class_count = 2; + const int class_sizes[class_count] = {1, 2}; + /* Compute the total number of registers across all classes. */ int ra_reg_count = 0; for (int i = 0; i < class_count; i++) { @@ -150,8 +154,6 @@ vec4_visitor::reg_allocate() unsigned int hw_reg_mapping[virtual_grf_count]; int first_assigned_grf = this->first_non_payload_grf; int base_reg_count = max_grf - first_assigned_grf; - int class_sizes[base_reg_count]; - int class_count = 0; /* Using the trivial allocator can be useful in debugging undefined * register access as a result of broken optimization passes. @@ -161,42 +163,16 @@ vec4_visitor::reg_allocate() calculate_live_intervals(); - /* Set up the register classes. - * - * The base registers store a vec4. However, we'll need larger - * storage for arrays, structures, and matrices, which will be sets - * of contiguous registers. - */ - class_sizes[class_count++] = 1; - - for (int r = 0; r < virtual_grf_count; r++) { - int i; - - for (i = 0; i < class_count; i++) { - if (class_sizes[i] == this->virtual_grf_sizes[r]) - break; - } - if (i == class_count) { - if (this->virtual_grf_sizes[r] >= base_reg_count) { - fail("Object too large to register allocate.\n"); - } - - class_sizes[class_count++] = this->virtual_grf_sizes[r]; - } - } - - brw_alloc_reg_set_for_classes(brw, class_sizes, class_count, base_reg_count); + brw_alloc_reg_set(brw, base_reg_count); struct ra_graph *g = ra_alloc_interference_graph(brw->vs.regs, virtual_grf_count); for (int i = 0; i < virtual_grf_count; i++) { - for (int c = 0; c < class_count; c++) { - if (class_sizes[c] == this->virtual_grf_sizes[i]) { - ra_set_node_class(g, i, brw->vs.classes[c]); - break; - } - } + int size = this->virtual_grf_sizes[i]; + assert(size >= 1 && size <= 2 && + "Register allocation relies on split_virtual_grfs()."); + ra_set_node_class(g, i, brw->vs.classes[size - 1]); for (int j = 0; j < i; j++) { if (virtual_grf_interferes(i, j)) { -- 2.30.2