[Mesa-dev] [PATCH] mesa: Move register_allocate.c to util.
Roland Scheidegger
sroland at vmware.com
Tue Sep 23 15:26:17 PDT 2014
This change seems to cause compile failure with scons:
Compiling src/util/register_allocate.c ...
src/util/register_allocate.c:76:26: fatal error: main/imports.h: No such
file or directory
#include "main/imports.h"
Looks like it could be fixed by patching up the CPPPATH in the
SConscript file though I don't think it's actually a good idea to have
the util code which was meant to be outside of classic mesa to depend on
includes in there?
Roland
Am 23.09.2014 02:32, schrieb Eric Anholt:
> The r300 gallium driver is using it outside of the Mesa tree, and I wanted
> to do so for vc4 as well. Rather than make the multiple-definitions
> problem even more complicated, just move it to more-shared code.
> ---
> src/gallium/drivers/r300/Makefile.am | 14 +-
> src/gallium/drivers/r300/Makefile.sources | 3 -
> .../drivers/r300/compiler/radeon_pair_regalloc.c | 2 +-
> src/mesa/Makefile.sources | 1 -
> src/mesa/drivers/dri/i965/brw_fs.cpp | 2 +-
> src/mesa/drivers/dri/i965/brw_fs.h | 2 +-
> src/mesa/drivers/dri/i965/brw_fs_visitor.cpp | 2 +-
> .../drivers/dri/i965/brw_vec4_reg_allocate.cpp | 2 +-
> src/mesa/program/register_allocate.c | 654 ---------------------
> src/mesa/program/register_allocate.h | 79 ---
> src/util/Makefile.am | 3 +
> src/util/Makefile.sources | 2 +
> src/util/register_allocate.c | 654 +++++++++++++++++++++
> src/util/register_allocate.h | 79 +++
> 14 files changed, 745 insertions(+), 754 deletions(-)
> delete mode 100644 src/mesa/program/register_allocate.c
> delete mode 100644 src/mesa/program/register_allocate.h
> create mode 100644 src/util/register_allocate.c
> create mode 100644 src/util/register_allocate.h
>
> diff --git a/src/gallium/drivers/r300/Makefile.am b/src/gallium/drivers/r300/Makefile.am
> index 7692bd8..ead7a87 100644
> --- a/src/gallium/drivers/r300/Makefile.am
> +++ b/src/gallium/drivers/r300/Makefile.am
> @@ -13,11 +13,11 @@ AM_CFLAGS = \
> $(LLVM_CFLAGS) \
> $(RADEON_CFLAGS)
>
> -noinst_LTLIBRARIES = libr300.la libr300-helper.la
> +noinst_LTLIBRARIES = libr300.la
> check_PROGRAMS = r300_compiler_tests
> TESTS = r300_compiler_tests
>
> -r300_compiler_tests_LDADD = libr300.la libr300-helper.la \
> +r300_compiler_tests_LDADD = libr300.la \
> $(top_builddir)/src/gallium/auxiliary/libgallium.la \
> $(top_builddir)/src/util/libmesautil.la \
> $(GALLIUM_COMMON_LIB_DEPS)
> @@ -28,16 +28,6 @@ r300_compiler_tests_SOURCES = $(COMPILER_TESTS_SOURCES)
>
> libr300_la_SOURCES = $(C_SOURCES)
>
> -# These two files are included in libmesagallium, which is included in the dri
> -# targets. So, they were added directly to r300g the dri-r300 target would have
> -# duplicated symbols, and if they weren't the other *-r300 targets would fail
> -# with undefined symbols.
> -#
> -# Solve this by building them into a separate helper library that can be linked
> -# in place of libmesagallium.
> -libr300_helper_la_CPPFLAGS = -I$(top_srcdir)/src
> -libr300_helper_la_SOURCES = $(HELPER_SOURCES)
> -
> EXTRA_DIST = Android.mk \
> compiler/tests/omod_two_writers.test \
> compiler/tests/regalloc_tex_1d_swizzle.test
> diff --git a/src/gallium/drivers/r300/Makefile.sources b/src/gallium/drivers/r300/Makefile.sources
> index ab1c9de..1ba6db0 100644
> --- a/src/gallium/drivers/r300/Makefile.sources
> +++ b/src/gallium/drivers/r300/Makefile.sources
> @@ -108,6 +108,3 @@ COMPILER_TESTS_SOURCES := \
> compiler/tests/rc_test_helpers.h \
> compiler/tests/unit_test.c \
> compiler/tests/unit_test.h
> -
> -HELPER_SOURCES := \
> - register_allocate.c
> diff --git a/src/gallium/drivers/r300/compiler/radeon_pair_regalloc.c b/src/gallium/drivers/r300/compiler/radeon_pair_regalloc.c
> index b854a2f..64b225d 100644
> --- a/src/gallium/drivers/r300/compiler/radeon_pair_regalloc.c
> +++ b/src/gallium/drivers/r300/compiler/radeon_pair_regalloc.c
> @@ -31,7 +31,7 @@
> #include <stdio.h>
>
> #include "main/glheader.h"
> -#include "program/register_allocate.h"
> +#include "util/register_allocate.h"
> #include "util/u_memory.h"
> #include "util/ralloc.h"
>
> diff --git a/src/mesa/Makefile.sources b/src/mesa/Makefile.sources
> index 12336c0..4755018 100644
> --- a/src/mesa/Makefile.sources
> +++ b/src/mesa/Makefile.sources
> @@ -280,7 +280,6 @@ PROGRAM_FILES = \
> $(SRCDIR)program/prog_print.c \
> $(SRCDIR)program/prog_statevars.c \
> $(SRCDIR)program/programopt.c \
> - $(SRCDIR)program/register_allocate.c \
> $(SRCDIR)program/sampler.cpp \
> $(SRCDIR)program/string_to_uint_map.cpp \
> $(SRCDIR)program/symbol_table.c \
> diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp
> index fa95c81..5b628e0 100644
> --- a/src/mesa/drivers/dri/i965/brw_fs.cpp
> +++ b/src/mesa/drivers/dri/i965/brw_fs.cpp
> @@ -38,7 +38,7 @@ extern "C" {
> #include "main/fbobject.h"
> #include "program/prog_parameter.h"
> #include "program/prog_print.h"
> -#include "program/register_allocate.h"
> +#include "util/register_allocate.h"
> #include "program/sampler.h"
> #include "program/hash_table.h"
> #include "brw_context.h"
> diff --git a/src/mesa/drivers/dri/i965/brw_fs.h b/src/mesa/drivers/dri/i965/brw_fs.h
> index d40a2e3..5e0a426 100644
> --- a/src/mesa/drivers/dri/i965/brw_fs.h
> +++ b/src/mesa/drivers/dri/i965/brw_fs.h
> @@ -39,7 +39,7 @@ extern "C" {
> #include "program/prog_parameter.h"
> #include "program/prog_print.h"
> #include "program/prog_optimize.h"
> -#include "program/register_allocate.h"
> +#include "util/register_allocate.h"
> #include "program/sampler.h"
> #include "program/hash_table.h"
> #include "brw_context.h"
> diff --git a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
> index 2d5318a..54643c1 100644
> --- a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
> +++ b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
> @@ -36,7 +36,7 @@ extern "C" {
> #include "program/prog_parameter.h"
> #include "program/prog_print.h"
> #include "program/prog_optimize.h"
> -#include "program/register_allocate.h"
> +#include "util/register_allocate.h"
> #include "program/sampler.h"
> #include "program/hash_table.h"
> #include "brw_context.h"
> 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 ddab342..29feec0 100644
> --- a/src/mesa/drivers/dri/i965/brw_vec4_reg_allocate.cpp
> +++ b/src/mesa/drivers/dri/i965/brw_vec4_reg_allocate.cpp
> @@ -23,7 +23,7 @@
>
> extern "C" {
> #include "main/macros.h"
> -#include "program/register_allocate.h"
> +#include "util/register_allocate.h"
> } /* extern "C" */
>
> #include "brw_vec4.h"
> diff --git a/src/mesa/program/register_allocate.c b/src/mesa/program/register_allocate.c
> deleted file mode 100644
> index 7faf672..0000000
> --- a/src/mesa/program/register_allocate.c
> +++ /dev/null
> @@ -1,654 +0,0 @@
> -/*
> - * Copyright © 2010 Intel Corporation
> - *
> - * Permission is hereby granted, free of charge, to any person obtaining a
> - * copy of this software and associated documentation files (the "Software"),
> - * to deal in the Software without restriction, including without limitation
> - * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> - * and/or sell copies of the Software, and to permit persons to whom the
> - * Software is furnished to do so, subject to the following conditions:
> - *
> - * The above copyright notice and this permission notice (including the next
> - * paragraph) shall be included in all copies or substantial portions of the
> - * Software.
> - *
> - * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> - * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> - * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
> - * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> - * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
> - * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
> - * IN THE SOFTWARE.
> - *
> - * Authors:
> - * Eric Anholt <eric at anholt.net>
> - *
> - */
> -
> -/** @file register_allocate.c
> - *
> - * Graph-coloring register allocator.
> - *
> - * The basic idea of graph coloring is to make a node in a graph for
> - * every thing that needs a register (color) number assigned, and make
> - * edges in the graph between nodes that interfere (can't be allocated
> - * to the same register at the same time).
> - *
> - * During the "simplify" process, any any node with fewer edges than
> - * there are registers means that that edge can get assigned a
> - * register regardless of what its neighbors choose, so that node is
> - * pushed on a stack and removed (with its edges) from the graph.
> - * That likely causes other nodes to become trivially colorable as well.
> - *
> - * Then during the "select" process, nodes are popped off of that
> - * stack, their edges restored, and assigned a color different from
> - * their neighbors. Because they were pushed on the stack only when
> - * they were trivially colorable, any color chosen won't interfere
> - * with the registers to be popped later.
> - *
> - * The downside to most graph coloring is that real hardware often has
> - * limitations, like registers that need to be allocated to a node in
> - * pairs, or aligned on some boundary. This implementation follows
> - * the paper "Retargetable Graph-Coloring Register Allocation for
> - * Irregular Architectures" by Johan Runeson and Sven-Olof Nyström.
> - *
> - * In this system, there are register classes each containing various
> - * registers, and registers may interfere with other registers. For
> - * example, one might have a class of base registers, and a class of
> - * aligned register pairs that would each interfere with their pair of
> - * the base registers. Each node has a register class it needs to be
> - * assigned to. Define p(B) to be the size of register class B, and
> - * q(B,C) to be the number of registers in B that the worst choice
> - * register in C could conflict with. Then, this system replaces the
> - * basic graph coloring test of "fewer edges from this node than there
> - * are registers" with "For this node of class B, the sum of q(B,C)
> - * for each neighbor node of class C is less than pB".
> - *
> - * A nice feature of the pq test is that q(B,C) can be computed once
> - * up front and stored in a 2-dimensional array, so that the cost of
> - * coloring a node is constant with the number of registers. We do
> - * this during ra_set_finalize().
> - */
> -
> -#include <stdbool.h>
> -
> -#include "util/ralloc.h"
> -#include "main/imports.h"
> -#include "main/macros.h"
> -#include "main/mtypes.h"
> -#include "main/bitset.h"
> -#include "register_allocate.h"
> -
> -#define NO_REG ~0
> -
> -struct ra_reg {
> - BITSET_WORD *conflicts;
> - unsigned int *conflict_list;
> - unsigned int conflict_list_size;
> - unsigned int num_conflicts;
> -};
> -
> -struct ra_regs {
> - struct ra_reg *regs;
> - unsigned int count;
> -
> - struct ra_class **classes;
> - unsigned int class_count;
> -
> - bool round_robin;
> -};
> -
> -struct ra_class {
> - /**
> - * Bitset indicating which registers belong to this class.
> - *
> - * (If bit N is set, then register N belongs to this class.)
> - */
> - BITSET_WORD *regs;
> -
> - /**
> - * p(B) in Runeson/Nyström paper.
> - *
> - * This is "how many regs are in the set."
> - */
> - unsigned int p;
> -
> - /**
> - * q(B,C) (indexed by C, B is this register class) in
> - * Runeson/Nyström paper. This is "how many registers of B could
> - * the worst choice register from C conflict with".
> - */
> - unsigned int *q;
> -};
> -
> -struct ra_node {
> - /** @{
> - *
> - * List of which nodes this node interferes with. This should be
> - * symmetric with the other node.
> - */
> - BITSET_WORD *adjacency;
> - unsigned int *adjacency_list;
> - unsigned int adjacency_list_size;
> - unsigned int adjacency_count;
> - /** @} */
> -
> - unsigned int class;
> -
> - /* Register, if assigned, or NO_REG. */
> - unsigned int reg;
> -
> - /**
> - * Set when the node is in the trivially colorable stack. When
> - * set, the adjacency to this node is ignored, to implement the
> - * "remove the edge from the graph" in simplification without
> - * having to actually modify the adjacency_list.
> - */
> - bool in_stack;
> -
> - /**
> - * The q total, as defined in the Runeson/Nyström paper, for all the
> - * interfering nodes not in the stack.
> - */
> - unsigned int q_total;
> -
> - /* For an implementation that needs register spilling, this is the
> - * approximate cost of spilling this node.
> - */
> - float spill_cost;
> -};
> -
> -struct ra_graph {
> - struct ra_regs *regs;
> - /**
> - * the variables that need register allocation.
> - */
> - struct ra_node *nodes;
> - unsigned int count; /**< count of nodes. */
> -
> - unsigned int *stack;
> - unsigned int stack_count;
> -};
> -
> -/**
> - * Creates a set of registers for the allocator.
> - *
> - * mem_ctx is a ralloc context for the allocator. The reg set may be freed
> - * using ralloc_free().
> - */
> -struct ra_regs *
> -ra_alloc_reg_set(void *mem_ctx, unsigned int count)
> -{
> - unsigned int i;
> - struct ra_regs *regs;
> -
> - regs = rzalloc(mem_ctx, struct ra_regs);
> - regs->count = count;
> - regs->regs = rzalloc_array(regs, struct ra_reg, count);
> -
> - for (i = 0; i < count; i++) {
> - regs->regs[i].conflicts = rzalloc_array(regs->regs, BITSET_WORD,
> - BITSET_WORDS(count));
> - BITSET_SET(regs->regs[i].conflicts, i);
> -
> - regs->regs[i].conflict_list = ralloc_array(regs->regs, unsigned int, 4);
> - regs->regs[i].conflict_list_size = 4;
> - regs->regs[i].conflict_list[0] = i;
> - regs->regs[i].num_conflicts = 1;
> - }
> -
> - return regs;
> -}
> -
> -/**
> - * The register allocator by default prefers to allocate low register numbers,
> - * since it was written for hardware (gen4/5 Intel) that is limited in its
> - * multithreadedness by the number of registers used in a given shader.
> - *
> - * However, for hardware without that restriction, densely packed register
> - * allocation can put serious constraints on instruction scheduling. This
> - * function tells the allocator to rotate around the registers if possible as
> - * it allocates the nodes.
> - */
> -void
> -ra_set_allocate_round_robin(struct ra_regs *regs)
> -{
> - regs->round_robin = true;
> -}
> -
> -static void
> -ra_add_conflict_list(struct ra_regs *regs, unsigned int r1, unsigned int r2)
> -{
> - struct ra_reg *reg1 = ®s->regs[r1];
> -
> - if (reg1->conflict_list_size == reg1->num_conflicts) {
> - reg1->conflict_list_size *= 2;
> - reg1->conflict_list = reralloc(regs->regs, reg1->conflict_list,
> - unsigned int, reg1->conflict_list_size);
> - }
> - reg1->conflict_list[reg1->num_conflicts++] = r2;
> - BITSET_SET(reg1->conflicts, r2);
> -}
> -
> -void
> -ra_add_reg_conflict(struct ra_regs *regs, unsigned int r1, unsigned int r2)
> -{
> - if (!BITSET_TEST(regs->regs[r1].conflicts, r2)) {
> - ra_add_conflict_list(regs, r1, r2);
> - ra_add_conflict_list(regs, r2, r1);
> - }
> -}
> -
> -/**
> - * Adds a conflict between base_reg and reg, and also between reg and
> - * anything that base_reg conflicts with.
> - *
> - * This can simplify code for setting up multiple register classes
> - * which are aggregates of some base hardware registers, compared to
> - * explicitly using ra_add_reg_conflict.
> - */
> -void
> -ra_add_transitive_reg_conflict(struct ra_regs *regs,
> - unsigned int base_reg, unsigned int reg)
> -{
> - int i;
> -
> - ra_add_reg_conflict(regs, reg, base_reg);
> -
> - for (i = 0; i < regs->regs[base_reg].num_conflicts; i++) {
> - ra_add_reg_conflict(regs, reg, regs->regs[base_reg].conflict_list[i]);
> - }
> -}
> -
> -unsigned int
> -ra_alloc_reg_class(struct ra_regs *regs)
> -{
> - struct ra_class *class;
> -
> - regs->classes = reralloc(regs->regs, regs->classes, struct ra_class *,
> - regs->class_count + 1);
> -
> - class = rzalloc(regs, struct ra_class);
> - regs->classes[regs->class_count] = class;
> -
> - class->regs = rzalloc_array(class, BITSET_WORD, BITSET_WORDS(regs->count));
> -
> - return regs->class_count++;
> -}
> -
> -void
> -ra_class_add_reg(struct ra_regs *regs, unsigned int c, unsigned int r)
> -{
> - struct ra_class *class = regs->classes[c];
> -
> - BITSET_SET(class->regs, r);
> - class->p++;
> -}
> -
> -/**
> - * Returns true if the register belongs to the given class.
> - */
> -static bool
> -reg_belongs_to_class(unsigned int r, struct ra_class *c)
> -{
> - return BITSET_TEST(c->regs, r);
> -}
> -
> -/**
> - * Must be called after all conflicts and register classes have been
> - * set up and before the register set is used for allocation.
> - * To avoid costly q value computation, use the q_values paramater
> - * to pass precomputed q values to this function.
> - */
> -void
> -ra_set_finalize(struct ra_regs *regs, unsigned int **q_values)
> -{
> - unsigned int b, c;
> -
> - for (b = 0; b < regs->class_count; b++) {
> - regs->classes[b]->q = ralloc_array(regs, unsigned int, regs->class_count);
> - }
> -
> - if (q_values) {
> - for (b = 0; b < regs->class_count; b++) {
> - for (c = 0; c < regs->class_count; c++) {
> - regs->classes[b]->q[c] = q_values[b][c];
> - }
> - }
> - return;
> - }
> -
> - /* Compute, for each class B and C, how many regs of B an
> - * allocation to C could conflict with.
> - */
> - for (b = 0; b < regs->class_count; b++) {
> - for (c = 0; c < regs->class_count; c++) {
> - unsigned int rc;
> - int max_conflicts = 0;
> -
> - for (rc = 0; rc < regs->count; rc++) {
> - int conflicts = 0;
> - int i;
> -
> - if (!reg_belongs_to_class(rc, regs->classes[c]))
> - continue;
> -
> - for (i = 0; i < regs->regs[rc].num_conflicts; i++) {
> - unsigned int rb = regs->regs[rc].conflict_list[i];
> - if (BITSET_TEST(regs->classes[b]->regs, rb))
> - conflicts++;
> - }
> - max_conflicts = MAX2(max_conflicts, conflicts);
> - }
> - regs->classes[b]->q[c] = max_conflicts;
> - }
> - }
> -}
> -
> -static void
> -ra_add_node_adjacency(struct ra_graph *g, unsigned int n1, unsigned int n2)
> -{
> - BITSET_SET(g->nodes[n1].adjacency, n2);
> -
> - if (n1 != n2) {
> - int n1_class = g->nodes[n1].class;
> - int n2_class = g->nodes[n2].class;
> - g->nodes[n1].q_total += g->regs->classes[n1_class]->q[n2_class];
> - }
> -
> - if (g->nodes[n1].adjacency_count >=
> - g->nodes[n1].adjacency_list_size) {
> - g->nodes[n1].adjacency_list_size *= 2;
> - g->nodes[n1].adjacency_list = reralloc(g, g->nodes[n1].adjacency_list,
> - unsigned int,
> - g->nodes[n1].adjacency_list_size);
> - }
> -
> - g->nodes[n1].adjacency_list[g->nodes[n1].adjacency_count] = n2;
> - g->nodes[n1].adjacency_count++;
> -}
> -
> -struct ra_graph *
> -ra_alloc_interference_graph(struct ra_regs *regs, unsigned int count)
> -{
> - struct ra_graph *g;
> - unsigned int i;
> -
> - g = rzalloc(regs, struct ra_graph);
> - g->regs = regs;
> - g->nodes = rzalloc_array(g, struct ra_node, count);
> - g->count = count;
> -
> - g->stack = rzalloc_array(g, unsigned int, count);
> -
> - for (i = 0; i < count; i++) {
> - int bitset_count = BITSET_WORDS(count);
> - g->nodes[i].adjacency = rzalloc_array(g, BITSET_WORD, bitset_count);
> -
> - g->nodes[i].adjacency_list_size = 4;
> - g->nodes[i].adjacency_list =
> - ralloc_array(g, unsigned int, g->nodes[i].adjacency_list_size);
> - g->nodes[i].adjacency_count = 0;
> - g->nodes[i].q_total = 0;
> -
> - ra_add_node_adjacency(g, i, i);
> - g->nodes[i].reg = NO_REG;
> - }
> -
> - return g;
> -}
> -
> -void
> -ra_set_node_class(struct ra_graph *g,
> - unsigned int n, unsigned int class)
> -{
> - g->nodes[n].class = class;
> -}
> -
> -void
> -ra_add_node_interference(struct ra_graph *g,
> - unsigned int n1, unsigned int n2)
> -{
> - if (!BITSET_TEST(g->nodes[n1].adjacency, n2)) {
> - ra_add_node_adjacency(g, n1, n2);
> - ra_add_node_adjacency(g, n2, n1);
> - }
> -}
> -
> -static bool
> -pq_test(struct ra_graph *g, unsigned int n)
> -{
> - int n_class = g->nodes[n].class;
> -
> - return g->nodes[n].q_total < g->regs->classes[n_class]->p;
> -}
> -
> -static void
> -decrement_q(struct ra_graph *g, unsigned int n)
> -{
> - unsigned int i;
> - int n_class = g->nodes[n].class;
> -
> - for (i = 0; i < g->nodes[n].adjacency_count; i++) {
> - unsigned int n2 = g->nodes[n].adjacency_list[i];
> - unsigned int n2_class = g->nodes[n2].class;
> -
> - if (n != n2 && !g->nodes[n2].in_stack) {
> - assert(g->nodes[n2].q_total >= g->regs->classes[n2_class]->q[n_class]);
> - g->nodes[n2].q_total -= g->regs->classes[n2_class]->q[n_class];
> - }
> - }
> -}
> -
> -/**
> - * Simplifies the interference graph by pushing all
> - * trivially-colorable nodes into a stack of nodes to be colored,
> - * removing them from the graph, and rinsing and repeating.
> - *
> - * If we encounter a case where we can't push any nodes on the stack, then
> - * we optimistically choose a node and push it on the stack. We heuristically
> - * push the node with the lowest total q value, since it has the fewest
> - * neighbors and therefore is most likely to be allocated.
> - */
> -static void
> -ra_simplify(struct ra_graph *g)
> -{
> - bool progress = true;
> - int i;
> -
> - while (progress) {
> - unsigned int best_optimistic_node = ~0;
> - unsigned int lowest_q_total = ~0;
> -
> - progress = false;
> -
> - for (i = g->count - 1; i >= 0; i--) {
> - if (g->nodes[i].in_stack || g->nodes[i].reg != NO_REG)
> - continue;
> -
> - if (pq_test(g, i)) {
> - decrement_q(g, i);
> - g->stack[g->stack_count] = i;
> - g->stack_count++;
> - g->nodes[i].in_stack = true;
> - progress = true;
> - } else {
> - unsigned int new_q_total = g->nodes[i].q_total;
> - if (new_q_total < lowest_q_total) {
> - best_optimistic_node = i;
> - lowest_q_total = new_q_total;
> - }
> - }
> - }
> -
> - if (!progress && best_optimistic_node != ~0) {
> - decrement_q(g, best_optimistic_node);
> - g->stack[g->stack_count] = best_optimistic_node;
> - g->stack_count++;
> - g->nodes[best_optimistic_node].in_stack = true;
> - progress = true;
> - }
> - }
> -}
> -
> -/**
> - * Pops nodes from the stack back into the graph, coloring them with
> - * registers as they go.
> - *
> - * If all nodes were trivially colorable, then this must succeed. If
> - * not (optimistic coloring), then it may return false;
> - */
> -static bool
> -ra_select(struct ra_graph *g)
> -{
> - int i;
> - int start_search_reg = 0;
> -
> - while (g->stack_count != 0) {
> - unsigned int ri;
> - unsigned int r = -1;
> - int n = g->stack[g->stack_count - 1];
> - struct ra_class *c = g->regs->classes[g->nodes[n].class];
> -
> - /* Find the lowest-numbered reg which is not used by a member
> - * of the graph adjacent to us.
> - */
> - for (ri = 0; ri < g->regs->count; ri++) {
> - r = (start_search_reg + ri) % g->regs->count;
> - if (!reg_belongs_to_class(r, c))
> - continue;
> -
> - /* Check if any of our neighbors conflict with this register choice. */
> - for (i = 0; i < g->nodes[n].adjacency_count; i++) {
> - unsigned int n2 = g->nodes[n].adjacency_list[i];
> -
> - if (!g->nodes[n2].in_stack &&
> - BITSET_TEST(g->regs->regs[r].conflicts, g->nodes[n2].reg)) {
> - break;
> - }
> - }
> - if (i == g->nodes[n].adjacency_count)
> - break;
> - }
> -
> - /* set this to false even if we return here so that
> - * ra_get_best_spill_node() considers this node later.
> - */
> - g->nodes[n].in_stack = false;
> -
> - if (ri == g->regs->count)
> - return false;
> -
> - g->nodes[n].reg = r;
> - g->stack_count--;
> -
> - if (g->regs->round_robin)
> - start_search_reg = r + 1;
> - }
> -
> - return true;
> -}
> -
> -bool
> -ra_allocate(struct ra_graph *g)
> -{
> - ra_simplify(g);
> - return ra_select(g);
> -}
> -
> -unsigned int
> -ra_get_node_reg(struct ra_graph *g, unsigned int n)
> -{
> - return g->nodes[n].reg;
> -}
> -
> -/**
> - * Forces a node to a specific register. This can be used to avoid
> - * creating a register class containing one node when handling data
> - * that must live in a fixed location and is known to not conflict
> - * with other forced register assignment (as is common with shader
> - * input data). These nodes do not end up in the stack during
> - * ra_simplify(), and thus at ra_select() time it is as if they were
> - * the first popped off the stack and assigned their fixed locations.
> - * Nodes that use this function do not need to be assigned a register
> - * class.
> - *
> - * Must be called before ra_simplify().
> - */
> -void
> -ra_set_node_reg(struct ra_graph *g, unsigned int n, unsigned int reg)
> -{
> - g->nodes[n].reg = reg;
> - g->nodes[n].in_stack = false;
> -}
> -
> -static float
> -ra_get_spill_benefit(struct ra_graph *g, unsigned int n)
> -{
> - int j;
> - float benefit = 0;
> - int n_class = g->nodes[n].class;
> -
> - /* Define the benefit of eliminating an interference between n, n2
> - * through spilling as q(C, B) / p(C). This is similar to the
> - * "count number of edges" approach of traditional graph coloring,
> - * but takes classes into account.
> - */
> - for (j = 0; j < g->nodes[n].adjacency_count; j++) {
> - unsigned int n2 = g->nodes[n].adjacency_list[j];
> - if (n != n2) {
> - unsigned int n2_class = g->nodes[n2].class;
> - benefit += ((float)g->regs->classes[n_class]->q[n2_class] /
> - g->regs->classes[n_class]->p);
> - }
> - }
> -
> - return benefit;
> -}
> -
> -/**
> - * Returns a node number to be spilled according to the cost/benefit using
> - * the pq test, or -1 if there are no spillable nodes.
> - */
> -int
> -ra_get_best_spill_node(struct ra_graph *g)
> -{
> - unsigned int best_node = -1;
> - float best_benefit = 0.0;
> - unsigned int n;
> -
> - /* Consider any nodes that we colored successfully or the node we failed to
> - * color for spilling. When we failed to color a node in ra_select(), we
> - * only considered these nodes, so spilling any other ones would not result
> - * in us making progress.
> - */
> - for (n = 0; n < g->count; n++) {
> - float cost = g->nodes[n].spill_cost;
> - float benefit;
> -
> - if (cost <= 0.0)
> - continue;
> -
> - if (g->nodes[n].in_stack)
> - continue;
> -
> - benefit = ra_get_spill_benefit(g, n);
> -
> - if (benefit / cost > best_benefit) {
> - best_benefit = benefit / cost;
> - best_node = n;
> - }
> - }
> -
> - return best_node;
> -}
> -
> -/**
> - * Only nodes with a spill cost set (cost != 0.0) will be considered
> - * for register spilling.
> - */
> -void
> -ra_set_node_spill_cost(struct ra_graph *g, unsigned int n, float cost)
> -{
> - g->nodes[n].spill_cost = cost;
> -}
> diff --git a/src/mesa/program/register_allocate.h b/src/mesa/program/register_allocate.h
> deleted file mode 100644
> index dc68744..0000000
> --- a/src/mesa/program/register_allocate.h
> +++ /dev/null
> @@ -1,79 +0,0 @@
> -/*
> - * Copyright © 2010 Intel Corporation
> - *
> - * Permission is hereby granted, free of charge, to any person obtaining a
> - * copy of this software and associated documentation files (the "Software"),
> - * to deal in the Software without restriction, including without limitation
> - * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> - * and/or sell copies of the Software, and to permit persons to whom the
> - * Software is furnished to do so, subject to the following conditions:
> - *
> - * The above copyright notice and this permission notice (including the next
> - * paragraph) shall be included in all copies or substantial portions of the
> - * Software.
> - *
> - * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> - * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> - * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
> - * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> - * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
> - * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
> - * IN THE SOFTWARE.
> - *
> - * Authors:
> - * Eric Anholt <eric at anholt.net>
> - *
> - */
> -
> -#include <stdbool.h>
> -
> -struct ra_class;
> -struct ra_regs;
> -
> -/* @{
> - * Register set setup.
> - *
> - * This should be done once at backend initializaion, as
> - * ra_set_finalize is O(r^2*c^2). The registers may be virtual
> - * registers, such as aligned register pairs that conflict with the
> - * two real registers from which they are composed.
> - */
> -struct ra_regs *ra_alloc_reg_set(void *mem_ctx, unsigned int count);
> -void ra_set_allocate_round_robin(struct ra_regs *regs);
> -unsigned int ra_alloc_reg_class(struct ra_regs *regs);
> -void ra_add_reg_conflict(struct ra_regs *regs,
> - unsigned int r1, unsigned int r2);
> -void ra_add_transitive_reg_conflict(struct ra_regs *regs,
> - unsigned int base_reg, unsigned int reg);
> -void ra_class_add_reg(struct ra_regs *regs, unsigned int c, unsigned int reg);
> -void ra_set_num_conflicts(struct ra_regs *regs, unsigned int class_a,
> - unsigned int class_b, unsigned int num_conflicts);
> -void ra_set_finalize(struct ra_regs *regs, unsigned int **conflicts);
> -/** @} */
> -
> -/** @{ Interference graph setup.
> - *
> - * Each interference graph node is a virtual variable in the IL. It
> - * is up to the user to ra_set_node_class() for the virtual variable,
> - * and compute live ranges and ra_node_interfere() between conflicting
> - * live ranges. Note that an interference *must not* be added between
> - * two nodes if their classes haven't been assigned yet. The user
> - * should set the class of each node before building the interference
> - * graph.
> - */
> -struct ra_graph *ra_alloc_interference_graph(struct ra_regs *regs,
> - unsigned int count);
> -void ra_set_node_class(struct ra_graph *g, unsigned int n, unsigned int c);
> -void ra_add_node_interference(struct ra_graph *g,
> - unsigned int n1, unsigned int n2);
> -/** @} */
> -
> -/** @{ Graph-coloring register allocation */
> -bool ra_allocate(struct ra_graph *g);
> -
> -unsigned int ra_get_node_reg(struct ra_graph *g, unsigned int n);
> -void ra_set_node_reg(struct ra_graph * g, unsigned int n, unsigned int reg);
> -void ra_set_node_spill_cost(struct ra_graph *g, unsigned int n, float cost);
> -int ra_get_best_spill_node(struct ra_graph *g);
> -/** @} */
> -
> diff --git a/src/util/Makefile.am b/src/util/Makefile.am
> index 4733a1a..8d5f90e 100644
> --- a/src/util/Makefile.am
> +++ b/src/util/Makefile.am
> @@ -28,6 +28,9 @@ noinst_LTLIBRARIES = libmesautil.la
> libmesautil_la_CPPFLAGS = \
> $(DEFINES) \
> -I$(top_srcdir)/include \
> + -I$(top_srcdir)/src \
> + -I$(top_srcdir)/src/mapi \
> + -I$(top_srcdir)/src/mesa \
> $(VISIBILITY_CFLAGS)
>
> libmesautil_la_SOURCES = \
> diff --git a/src/util/Makefile.sources b/src/util/Makefile.sources
> index c34475a..952b799 100644
> --- a/src/util/Makefile.sources
> +++ b/src/util/Makefile.sources
> @@ -1,6 +1,8 @@
> MESA_UTIL_FILES := \
> hash_table.c \
> ralloc.c \
> + register_allocate.c \
> + register_allocate.h \
> rgtc.c
>
> MESA_UTIL_GENERATED_FILES = \
> diff --git a/src/util/register_allocate.c b/src/util/register_allocate.c
> new file mode 100644
> index 0000000..7faf672
> --- /dev/null
> +++ b/src/util/register_allocate.c
> @@ -0,0 +1,654 @@
> +/*
> + * Copyright © 2010 Intel Corporation
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice (including the next
> + * paragraph) shall be included in all copies or substantial portions of the
> + * Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
> + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
> + * IN THE SOFTWARE.
> + *
> + * Authors:
> + * Eric Anholt <eric at anholt.net>
> + *
> + */
> +
> +/** @file register_allocate.c
> + *
> + * Graph-coloring register allocator.
> + *
> + * The basic idea of graph coloring is to make a node in a graph for
> + * every thing that needs a register (color) number assigned, and make
> + * edges in the graph between nodes that interfere (can't be allocated
> + * to the same register at the same time).
> + *
> + * During the "simplify" process, any any node with fewer edges than
> + * there are registers means that that edge can get assigned a
> + * register regardless of what its neighbors choose, so that node is
> + * pushed on a stack and removed (with its edges) from the graph.
> + * That likely causes other nodes to become trivially colorable as well.
> + *
> + * Then during the "select" process, nodes are popped off of that
> + * stack, their edges restored, and assigned a color different from
> + * their neighbors. Because they were pushed on the stack only when
> + * they were trivially colorable, any color chosen won't interfere
> + * with the registers to be popped later.
> + *
> + * The downside to most graph coloring is that real hardware often has
> + * limitations, like registers that need to be allocated to a node in
> + * pairs, or aligned on some boundary. This implementation follows
> + * the paper "Retargetable Graph-Coloring Register Allocation for
> + * Irregular Architectures" by Johan Runeson and Sven-Olof Nyström.
> + *
> + * In this system, there are register classes each containing various
> + * registers, and registers may interfere with other registers. For
> + * example, one might have a class of base registers, and a class of
> + * aligned register pairs that would each interfere with their pair of
> + * the base registers. Each node has a register class it needs to be
> + * assigned to. Define p(B) to be the size of register class B, and
> + * q(B,C) to be the number of registers in B that the worst choice
> + * register in C could conflict with. Then, this system replaces the
> + * basic graph coloring test of "fewer edges from this node than there
> + * are registers" with "For this node of class B, the sum of q(B,C)
> + * for each neighbor node of class C is less than pB".
> + *
> + * A nice feature of the pq test is that q(B,C) can be computed once
> + * up front and stored in a 2-dimensional array, so that the cost of
> + * coloring a node is constant with the number of registers. We do
> + * this during ra_set_finalize().
> + */
> +
> +#include <stdbool.h>
> +
> +#include "util/ralloc.h"
> +#include "main/imports.h"
> +#include "main/macros.h"
> +#include "main/mtypes.h"
> +#include "main/bitset.h"
> +#include "register_allocate.h"
> +
> +#define NO_REG ~0
> +
> +struct ra_reg {
> + BITSET_WORD *conflicts;
> + unsigned int *conflict_list;
> + unsigned int conflict_list_size;
> + unsigned int num_conflicts;
> +};
> +
> +struct ra_regs {
> + struct ra_reg *regs;
> + unsigned int count;
> +
> + struct ra_class **classes;
> + unsigned int class_count;
> +
> + bool round_robin;
> +};
> +
> +struct ra_class {
> + /**
> + * Bitset indicating which registers belong to this class.
> + *
> + * (If bit N is set, then register N belongs to this class.)
> + */
> + BITSET_WORD *regs;
> +
> + /**
> + * p(B) in Runeson/Nyström paper.
> + *
> + * This is "how many regs are in the set."
> + */
> + unsigned int p;
> +
> + /**
> + * q(B,C) (indexed by C, B is this register class) in
> + * Runeson/Nyström paper. This is "how many registers of B could
> + * the worst choice register from C conflict with".
> + */
> + unsigned int *q;
> +};
> +
> +struct ra_node {
> + /** @{
> + *
> + * List of which nodes this node interferes with. This should be
> + * symmetric with the other node.
> + */
> + BITSET_WORD *adjacency;
> + unsigned int *adjacency_list;
> + unsigned int adjacency_list_size;
> + unsigned int adjacency_count;
> + /** @} */
> +
> + unsigned int class;
> +
> + /* Register, if assigned, or NO_REG. */
> + unsigned int reg;
> +
> + /**
> + * Set when the node is in the trivially colorable stack. When
> + * set, the adjacency to this node is ignored, to implement the
> + * "remove the edge from the graph" in simplification without
> + * having to actually modify the adjacency_list.
> + */
> + bool in_stack;
> +
> + /**
> + * The q total, as defined in the Runeson/Nyström paper, for all the
> + * interfering nodes not in the stack.
> + */
> + unsigned int q_total;
> +
> + /* For an implementation that needs register spilling, this is the
> + * approximate cost of spilling this node.
> + */
> + float spill_cost;
> +};
> +
> +struct ra_graph {
> + struct ra_regs *regs;
> + /**
> + * the variables that need register allocation.
> + */
> + struct ra_node *nodes;
> + unsigned int count; /**< count of nodes. */
> +
> + unsigned int *stack;
> + unsigned int stack_count;
> +};
> +
> +/**
> + * Creates a set of registers for the allocator.
> + *
> + * mem_ctx is a ralloc context for the allocator. The reg set may be freed
> + * using ralloc_free().
> + */
> +struct ra_regs *
> +ra_alloc_reg_set(void *mem_ctx, unsigned int count)
> +{
> + unsigned int i;
> + struct ra_regs *regs;
> +
> + regs = rzalloc(mem_ctx, struct ra_regs);
> + regs->count = count;
> + regs->regs = rzalloc_array(regs, struct ra_reg, count);
> +
> + for (i = 0; i < count; i++) {
> + regs->regs[i].conflicts = rzalloc_array(regs->regs, BITSET_WORD,
> + BITSET_WORDS(count));
> + BITSET_SET(regs->regs[i].conflicts, i);
> +
> + regs->regs[i].conflict_list = ralloc_array(regs->regs, unsigned int, 4);
> + regs->regs[i].conflict_list_size = 4;
> + regs->regs[i].conflict_list[0] = i;
> + regs->regs[i].num_conflicts = 1;
> + }
> +
> + return regs;
> +}
> +
> +/**
> + * The register allocator by default prefers to allocate low register numbers,
> + * since it was written for hardware (gen4/5 Intel) that is limited in its
> + * multithreadedness by the number of registers used in a given shader.
> + *
> + * However, for hardware without that restriction, densely packed register
> + * allocation can put serious constraints on instruction scheduling. This
> + * function tells the allocator to rotate around the registers if possible as
> + * it allocates the nodes.
> + */
> +void
> +ra_set_allocate_round_robin(struct ra_regs *regs)
> +{
> + regs->round_robin = true;
> +}
> +
> +static void
> +ra_add_conflict_list(struct ra_regs *regs, unsigned int r1, unsigned int r2)
> +{
> + struct ra_reg *reg1 = ®s->regs[r1];
> +
> + if (reg1->conflict_list_size == reg1->num_conflicts) {
> + reg1->conflict_list_size *= 2;
> + reg1->conflict_list = reralloc(regs->regs, reg1->conflict_list,
> + unsigned int, reg1->conflict_list_size);
> + }
> + reg1->conflict_list[reg1->num_conflicts++] = r2;
> + BITSET_SET(reg1->conflicts, r2);
> +}
> +
> +void
> +ra_add_reg_conflict(struct ra_regs *regs, unsigned int r1, unsigned int r2)
> +{
> + if (!BITSET_TEST(regs->regs[r1].conflicts, r2)) {
> + ra_add_conflict_list(regs, r1, r2);
> + ra_add_conflict_list(regs, r2, r1);
> + }
> +}
> +
> +/**
> + * Adds a conflict between base_reg and reg, and also between reg and
> + * anything that base_reg conflicts with.
> + *
> + * This can simplify code for setting up multiple register classes
> + * which are aggregates of some base hardware registers, compared to
> + * explicitly using ra_add_reg_conflict.
> + */
> +void
> +ra_add_transitive_reg_conflict(struct ra_regs *regs,
> + unsigned int base_reg, unsigned int reg)
> +{
> + int i;
> +
> + ra_add_reg_conflict(regs, reg, base_reg);
> +
> + for (i = 0; i < regs->regs[base_reg].num_conflicts; i++) {
> + ra_add_reg_conflict(regs, reg, regs->regs[base_reg].conflict_list[i]);
> + }
> +}
> +
> +unsigned int
> +ra_alloc_reg_class(struct ra_regs *regs)
> +{
> + struct ra_class *class;
> +
> + regs->classes = reralloc(regs->regs, regs->classes, struct ra_class *,
> + regs->class_count + 1);
> +
> + class = rzalloc(regs, struct ra_class);
> + regs->classes[regs->class_count] = class;
> +
> + class->regs = rzalloc_array(class, BITSET_WORD, BITSET_WORDS(regs->count));
> +
> + return regs->class_count++;
> +}
> +
> +void
> +ra_class_add_reg(struct ra_regs *regs, unsigned int c, unsigned int r)
> +{
> + struct ra_class *class = regs->classes[c];
> +
> + BITSET_SET(class->regs, r);
> + class->p++;
> +}
> +
> +/**
> + * Returns true if the register belongs to the given class.
> + */
> +static bool
> +reg_belongs_to_class(unsigned int r, struct ra_class *c)
> +{
> + return BITSET_TEST(c->regs, r);
> +}
> +
> +/**
> + * Must be called after all conflicts and register classes have been
> + * set up and before the register set is used for allocation.
> + * To avoid costly q value computation, use the q_values paramater
> + * to pass precomputed q values to this function.
> + */
> +void
> +ra_set_finalize(struct ra_regs *regs, unsigned int **q_values)
> +{
> + unsigned int b, c;
> +
> + for (b = 0; b < regs->class_count; b++) {
> + regs->classes[b]->q = ralloc_array(regs, unsigned int, regs->class_count);
> + }
> +
> + if (q_values) {
> + for (b = 0; b < regs->class_count; b++) {
> + for (c = 0; c < regs->class_count; c++) {
> + regs->classes[b]->q[c] = q_values[b][c];
> + }
> + }
> + return;
> + }
> +
> + /* Compute, for each class B and C, how many regs of B an
> + * allocation to C could conflict with.
> + */
> + for (b = 0; b < regs->class_count; b++) {
> + for (c = 0; c < regs->class_count; c++) {
> + unsigned int rc;
> + int max_conflicts = 0;
> +
> + for (rc = 0; rc < regs->count; rc++) {
> + int conflicts = 0;
> + int i;
> +
> + if (!reg_belongs_to_class(rc, regs->classes[c]))
> + continue;
> +
> + for (i = 0; i < regs->regs[rc].num_conflicts; i++) {
> + unsigned int rb = regs->regs[rc].conflict_list[i];
> + if (BITSET_TEST(regs->classes[b]->regs, rb))
> + conflicts++;
> + }
> + max_conflicts = MAX2(max_conflicts, conflicts);
> + }
> + regs->classes[b]->q[c] = max_conflicts;
> + }
> + }
> +}
> +
> +static void
> +ra_add_node_adjacency(struct ra_graph *g, unsigned int n1, unsigned int n2)
> +{
> + BITSET_SET(g->nodes[n1].adjacency, n2);
> +
> + if (n1 != n2) {
> + int n1_class = g->nodes[n1].class;
> + int n2_class = g->nodes[n2].class;
> + g->nodes[n1].q_total += g->regs->classes[n1_class]->q[n2_class];
> + }
> +
> + if (g->nodes[n1].adjacency_count >=
> + g->nodes[n1].adjacency_list_size) {
> + g->nodes[n1].adjacency_list_size *= 2;
> + g->nodes[n1].adjacency_list = reralloc(g, g->nodes[n1].adjacency_list,
> + unsigned int,
> + g->nodes[n1].adjacency_list_size);
> + }
> +
> + g->nodes[n1].adjacency_list[g->nodes[n1].adjacency_count] = n2;
> + g->nodes[n1].adjacency_count++;
> +}
> +
> +struct ra_graph *
> +ra_alloc_interference_graph(struct ra_regs *regs, unsigned int count)
> +{
> + struct ra_graph *g;
> + unsigned int i;
> +
> + g = rzalloc(regs, struct ra_graph);
> + g->regs = regs;
> + g->nodes = rzalloc_array(g, struct ra_node, count);
> + g->count = count;
> +
> + g->stack = rzalloc_array(g, unsigned int, count);
> +
> + for (i = 0; i < count; i++) {
> + int bitset_count = BITSET_WORDS(count);
> + g->nodes[i].adjacency = rzalloc_array(g, BITSET_WORD, bitset_count);
> +
> + g->nodes[i].adjacency_list_size = 4;
> + g->nodes[i].adjacency_list =
> + ralloc_array(g, unsigned int, g->nodes[i].adjacency_list_size);
> + g->nodes[i].adjacency_count = 0;
> + g->nodes[i].q_total = 0;
> +
> + ra_add_node_adjacency(g, i, i);
> + g->nodes[i].reg = NO_REG;
> + }
> +
> + return g;
> +}
> +
> +void
> +ra_set_node_class(struct ra_graph *g,
> + unsigned int n, unsigned int class)
> +{
> + g->nodes[n].class = class;
> +}
> +
> +void
> +ra_add_node_interference(struct ra_graph *g,
> + unsigned int n1, unsigned int n2)
> +{
> + if (!BITSET_TEST(g->nodes[n1].adjacency, n2)) {
> + ra_add_node_adjacency(g, n1, n2);
> + ra_add_node_adjacency(g, n2, n1);
> + }
> +}
> +
> +static bool
> +pq_test(struct ra_graph *g, unsigned int n)
> +{
> + int n_class = g->nodes[n].class;
> +
> + return g->nodes[n].q_total < g->regs->classes[n_class]->p;
> +}
> +
> +static void
> +decrement_q(struct ra_graph *g, unsigned int n)
> +{
> + unsigned int i;
> + int n_class = g->nodes[n].class;
> +
> + for (i = 0; i < g->nodes[n].adjacency_count; i++) {
> + unsigned int n2 = g->nodes[n].adjacency_list[i];
> + unsigned int n2_class = g->nodes[n2].class;
> +
> + if (n != n2 && !g->nodes[n2].in_stack) {
> + assert(g->nodes[n2].q_total >= g->regs->classes[n2_class]->q[n_class]);
> + g->nodes[n2].q_total -= g->regs->classes[n2_class]->q[n_class];
> + }
> + }
> +}
> +
> +/**
> + * Simplifies the interference graph by pushing all
> + * trivially-colorable nodes into a stack of nodes to be colored,
> + * removing them from the graph, and rinsing and repeating.
> + *
> + * If we encounter a case where we can't push any nodes on the stack, then
> + * we optimistically choose a node and push it on the stack. We heuristically
> + * push the node with the lowest total q value, since it has the fewest
> + * neighbors and therefore is most likely to be allocated.
> + */
> +static void
> +ra_simplify(struct ra_graph *g)
> +{
> + bool progress = true;
> + int i;
> +
> + while (progress) {
> + unsigned int best_optimistic_node = ~0;
> + unsigned int lowest_q_total = ~0;
> +
> + progress = false;
> +
> + for (i = g->count - 1; i >= 0; i--) {
> + if (g->nodes[i].in_stack || g->nodes[i].reg != NO_REG)
> + continue;
> +
> + if (pq_test(g, i)) {
> + decrement_q(g, i);
> + g->stack[g->stack_count] = i;
> + g->stack_count++;
> + g->nodes[i].in_stack = true;
> + progress = true;
> + } else {
> + unsigned int new_q_total = g->nodes[i].q_total;
> + if (new_q_total < lowest_q_total) {
> + best_optimistic_node = i;
> + lowest_q_total = new_q_total;
> + }
> + }
> + }
> +
> + if (!progress && best_optimistic_node != ~0) {
> + decrement_q(g, best_optimistic_node);
> + g->stack[g->stack_count] = best_optimistic_node;
> + g->stack_count++;
> + g->nodes[best_optimistic_node].in_stack = true;
> + progress = true;
> + }
> + }
> +}
> +
> +/**
> + * Pops nodes from the stack back into the graph, coloring them with
> + * registers as they go.
> + *
> + * If all nodes were trivially colorable, then this must succeed. If
> + * not (optimistic coloring), then it may return false;
> + */
> +static bool
> +ra_select(struct ra_graph *g)
> +{
> + int i;
> + int start_search_reg = 0;
> +
> + while (g->stack_count != 0) {
> + unsigned int ri;
> + unsigned int r = -1;
> + int n = g->stack[g->stack_count - 1];
> + struct ra_class *c = g->regs->classes[g->nodes[n].class];
> +
> + /* Find the lowest-numbered reg which is not used by a member
> + * of the graph adjacent to us.
> + */
> + for (ri = 0; ri < g->regs->count; ri++) {
> + r = (start_search_reg + ri) % g->regs->count;
> + if (!reg_belongs_to_class(r, c))
> + continue;
> +
> + /* Check if any of our neighbors conflict with this register choice. */
> + for (i = 0; i < g->nodes[n].adjacency_count; i++) {
> + unsigned int n2 = g->nodes[n].adjacency_list[i];
> +
> + if (!g->nodes[n2].in_stack &&
> + BITSET_TEST(g->regs->regs[r].conflicts, g->nodes[n2].reg)) {
> + break;
> + }
> + }
> + if (i == g->nodes[n].adjacency_count)
> + break;
> + }
> +
> + /* set this to false even if we return here so that
> + * ra_get_best_spill_node() considers this node later.
> + */
> + g->nodes[n].in_stack = false;
> +
> + if (ri == g->regs->count)
> + return false;
> +
> + g->nodes[n].reg = r;
> + g->stack_count--;
> +
> + if (g->regs->round_robin)
> + start_search_reg = r + 1;
> + }
> +
> + return true;
> +}
> +
> +bool
> +ra_allocate(struct ra_graph *g)
> +{
> + ra_simplify(g);
> + return ra_select(g);
> +}
> +
> +unsigned int
> +ra_get_node_reg(struct ra_graph *g, unsigned int n)
> +{
> + return g->nodes[n].reg;
> +}
> +
> +/**
> + * Forces a node to a specific register. This can be used to avoid
> + * creating a register class containing one node when handling data
> + * that must live in a fixed location and is known to not conflict
> + * with other forced register assignment (as is common with shader
> + * input data). These nodes do not end up in the stack during
> + * ra_simplify(), and thus at ra_select() time it is as if they were
> + * the first popped off the stack and assigned their fixed locations.
> + * Nodes that use this function do not need to be assigned a register
> + * class.
> + *
> + * Must be called before ra_simplify().
> + */
> +void
> +ra_set_node_reg(struct ra_graph *g, unsigned int n, unsigned int reg)
> +{
> + g->nodes[n].reg = reg;
> + g->nodes[n].in_stack = false;
> +}
> +
> +static float
> +ra_get_spill_benefit(struct ra_graph *g, unsigned int n)
> +{
> + int j;
> + float benefit = 0;
> + int n_class = g->nodes[n].class;
> +
> + /* Define the benefit of eliminating an interference between n, n2
> + * through spilling as q(C, B) / p(C). This is similar to the
> + * "count number of edges" approach of traditional graph coloring,
> + * but takes classes into account.
> + */
> + for (j = 0; j < g->nodes[n].adjacency_count; j++) {
> + unsigned int n2 = g->nodes[n].adjacency_list[j];
> + if (n != n2) {
> + unsigned int n2_class = g->nodes[n2].class;
> + benefit += ((float)g->regs->classes[n_class]->q[n2_class] /
> + g->regs->classes[n_class]->p);
> + }
> + }
> +
> + return benefit;
> +}
> +
> +/**
> + * Returns a node number to be spilled according to the cost/benefit using
> + * the pq test, or -1 if there are no spillable nodes.
> + */
> +int
> +ra_get_best_spill_node(struct ra_graph *g)
> +{
> + unsigned int best_node = -1;
> + float best_benefit = 0.0;
> + unsigned int n;
> +
> + /* Consider any nodes that we colored successfully or the node we failed to
> + * color for spilling. When we failed to color a node in ra_select(), we
> + * only considered these nodes, so spilling any other ones would not result
> + * in us making progress.
> + */
> + for (n = 0; n < g->count; n++) {
> + float cost = g->nodes[n].spill_cost;
> + float benefit;
> +
> + if (cost <= 0.0)
> + continue;
> +
> + if (g->nodes[n].in_stack)
> + continue;
> +
> + benefit = ra_get_spill_benefit(g, n);
> +
> + if (benefit / cost > best_benefit) {
> + best_benefit = benefit / cost;
> + best_node = n;
> + }
> + }
> +
> + return best_node;
> +}
> +
> +/**
> + * Only nodes with a spill cost set (cost != 0.0) will be considered
> + * for register spilling.
> + */
> +void
> +ra_set_node_spill_cost(struct ra_graph *g, unsigned int n, float cost)
> +{
> + g->nodes[n].spill_cost = cost;
> +}
> diff --git a/src/util/register_allocate.h b/src/util/register_allocate.h
> new file mode 100644
> index 0000000..dc68744
> --- /dev/null
> +++ b/src/util/register_allocate.h
> @@ -0,0 +1,79 @@
> +/*
> + * Copyright © 2010 Intel Corporation
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice (including the next
> + * paragraph) shall be included in all copies or substantial portions of the
> + * Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
> + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
> + * IN THE SOFTWARE.
> + *
> + * Authors:
> + * Eric Anholt <eric at anholt.net>
> + *
> + */
> +
> +#include <stdbool.h>
> +
> +struct ra_class;
> +struct ra_regs;
> +
> +/* @{
> + * Register set setup.
> + *
> + * This should be done once at backend initializaion, as
> + * ra_set_finalize is O(r^2*c^2). The registers may be virtual
> + * registers, such as aligned register pairs that conflict with the
> + * two real registers from which they are composed.
> + */
> +struct ra_regs *ra_alloc_reg_set(void *mem_ctx, unsigned int count);
> +void ra_set_allocate_round_robin(struct ra_regs *regs);
> +unsigned int ra_alloc_reg_class(struct ra_regs *regs);
> +void ra_add_reg_conflict(struct ra_regs *regs,
> + unsigned int r1, unsigned int r2);
> +void ra_add_transitive_reg_conflict(struct ra_regs *regs,
> + unsigned int base_reg, unsigned int reg);
> +void ra_class_add_reg(struct ra_regs *regs, unsigned int c, unsigned int reg);
> +void ra_set_num_conflicts(struct ra_regs *regs, unsigned int class_a,
> + unsigned int class_b, unsigned int num_conflicts);
> +void ra_set_finalize(struct ra_regs *regs, unsigned int **conflicts);
> +/** @} */
> +
> +/** @{ Interference graph setup.
> + *
> + * Each interference graph node is a virtual variable in the IL. It
> + * is up to the user to ra_set_node_class() for the virtual variable,
> + * and compute live ranges and ra_node_interfere() between conflicting
> + * live ranges. Note that an interference *must not* be added between
> + * two nodes if their classes haven't been assigned yet. The user
> + * should set the class of each node before building the interference
> + * graph.
> + */
> +struct ra_graph *ra_alloc_interference_graph(struct ra_regs *regs,
> + unsigned int count);
> +void ra_set_node_class(struct ra_graph *g, unsigned int n, unsigned int c);
> +void ra_add_node_interference(struct ra_graph *g,
> + unsigned int n1, unsigned int n2);
> +/** @} */
> +
> +/** @{ Graph-coloring register allocation */
> +bool ra_allocate(struct ra_graph *g);
> +
> +unsigned int ra_get_node_reg(struct ra_graph *g, unsigned int n);
> +void ra_set_node_reg(struct ra_graph * g, unsigned int n, unsigned int reg);
> +void ra_set_node_spill_cost(struct ra_graph *g, unsigned int n, float cost);
> +int ra_get_best_spill_node(struct ra_graph *g);
> +/** @} */
> +
>
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