[Mesa-dev] [PATCH] mesa: Move register_allocate.c to util.
Brian Paul
brianp at vmware.com
Tue Sep 23 15:40:27 PDT 2014
I just pushed a quick fix to get things compiling again. I'm wondering
about that dependency too though.
-Brian
On 09/23/2014 04:26 PM, Roland Scheidegger wrote:
> 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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