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authormarha <marha@users.sourceforge.net>2014-10-12 21:11:32 +0200
committermarha <marha@users.sourceforge.net>2014-10-12 21:38:35 +0200
commit1a83b8e49a75e2dab63805de25e384e0e38c27ed (patch)
tree5280fe2a1bd2ce227e4bce9ce06134986e181de1 /mesalib/src/glsl
parent4aea4b223604c589828beb1145875a5fbcc41eed (diff)
parent9480392b8817f8bfa79cbc694ff039a73fc0a57f (diff)
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Merge remote-tracking branch 'origin/released'
Conflicts: mesalib/src/glsl/glsl_symbol_table.h mesalib/src/mesa/drivers/common/meta_blit.c xorg-server/dix/dispatch.c xorg-server/glx/indirect_dispatch.c xorg-server/glx/indirect_dispatch_swap.c xorg-server/mi/miexpose.c
Diffstat (limited to 'mesalib/src/glsl')
-rw-r--r--mesalib/src/glsl/Android.mk4
-rw-r--r--mesalib/src/glsl/Makefile.sources1
-rwxr-xr-xmesalib/src/glsl/builtin_functions.cpp73
-rw-r--r--mesalib/src/glsl/glsl_parser_extras.cpp1
-rwxr-xr-x[-rw-r--r--]mesalib/src/glsl/glsl_symbol_table.h33
-rw-r--r--mesalib/src/glsl/ir_optimization.h1
-rw-r--r--mesalib/src/glsl/link_varyings.cpp18
-rw-r--r--mesalib/src/glsl/loop_analysis.h17
-rw-r--r--mesalib/src/glsl/opt_minmax.cpp475
9 files changed, 560 insertions, 63 deletions
diff --git a/mesalib/src/glsl/Android.mk b/mesalib/src/glsl/Android.mk
index 7b1fa7e53..1cbc5c6d2 100644
--- a/mesalib/src/glsl/Android.mk
+++ b/mesalib/src/glsl/Android.mk
@@ -39,6 +39,7 @@ LOCAL_SRC_FILES := \
$(LIBGLSL_FILES)
LOCAL_C_INCLUDES := \
+ $(MESA_TOP)/src \
$(MESA_TOP)/src/mapi \
$(MESA_TOP)/src/mesa
@@ -59,10 +60,11 @@ LOCAL_SRC_FILES := \
$(GLSL_COMPILER_CXX_FILES)
LOCAL_C_INCLUDES := \
+ $(MESA_TOP)/src \
$(MESA_TOP)/src/mapi \
$(MESA_TOP)/src/mesa
-LOCAL_STATIC_LIBRARIES := libmesa_glsl libmesa_glsl_utils
+LOCAL_STATIC_LIBRARIES := libmesa_glsl libmesa_glsl_utils libmesa_util
LOCAL_MODULE_TAGS := eng
LOCAL_MODULE := glsl_compiler
diff --git a/mesalib/src/glsl/Makefile.sources b/mesalib/src/glsl/Makefile.sources
index bfb699353..0c55327d6 100644
--- a/mesalib/src/glsl/Makefile.sources
+++ b/mesalib/src/glsl/Makefile.sources
@@ -96,6 +96,7 @@ LIBGLSL_FILES = \
$(GLSL_SRCDIR)/opt_flip_matrices.cpp \
$(GLSL_SRCDIR)/opt_function_inlining.cpp \
$(GLSL_SRCDIR)/opt_if_simplification.cpp \
+ $(GLSL_SRCDIR)/opt_minmax.cpp \
$(GLSL_SRCDIR)/opt_noop_swizzle.cpp \
$(GLSL_SRCDIR)/opt_rebalance_tree.cpp \
$(GLSL_SRCDIR)/opt_redundant_jumps.cpp \
diff --git a/mesalib/src/glsl/builtin_functions.cpp b/mesalib/src/glsl/builtin_functions.cpp
index 2cdaddea7..4cd76f6b8 100755
--- a/mesalib/src/glsl/builtin_functions.cpp
+++ b/mesalib/src/glsl/builtin_functions.cpp
@@ -442,6 +442,7 @@ private:
ir_swizzle *matrix_elt(ir_variable *var, int col, int row);
ir_expression *asin_expr(ir_variable *x);
+ void do_atan(ir_factory &body, const glsl_type *type, ir_variable *res, operand y_over_x);
/**
* Call function \param f with parameters specified as the linked
@@ -2684,11 +2685,7 @@ builtin_builder::_atan2(const glsl_type *type)
ir_factory outer_then(&outer_if->then_instructions, mem_ctx);
/* Then...call atan(y/x) */
- ir_variable *y_over_x = outer_then.make_temp(glsl_type::float_type, "y_over_x");
- outer_then.emit(assign(y_over_x, div(y, x)));
- outer_then.emit(assign(r, mul(y_over_x, rsq(add(mul(y_over_x, y_over_x),
- imm(1.0f))))));
- outer_then.emit(assign(r, asin_expr(r)));
+ do_atan(body, glsl_type::float_type, r, div(y, x));
/* ...and fix it up: */
ir_if *inner_if = new(mem_ctx) ir_if(less(x, imm(0.0f)));
@@ -2711,17 +2708,65 @@ builtin_builder::_atan2(const glsl_type *type)
return sig;
}
+void
+builtin_builder::do_atan(ir_factory &body, const glsl_type *type, ir_variable *res, operand y_over_x)
+{
+ /*
+ * range-reduction, first step:
+ *
+ * / y_over_x if |y_over_x| <= 1.0;
+ * x = <
+ * \ 1.0 / y_over_x otherwise
+ */
+ ir_variable *x = body.make_temp(type, "atan_x");
+ body.emit(assign(x, div(min2(abs(y_over_x),
+ imm(1.0f)),
+ max2(abs(y_over_x),
+ imm(1.0f)))));
+
+ /*
+ * approximate atan by evaluating polynomial:
+ *
+ * x * 0.9999793128310355 - x^3 * 0.3326756418091246 +
+ * x^5 * 0.1938924977115610 - x^7 * 0.1173503194786851 +
+ * x^9 * 0.0536813784310406 - x^11 * 0.0121323213173444
+ */
+ ir_variable *tmp = body.make_temp(type, "atan_tmp");
+ body.emit(assign(tmp, mul(x, x)));
+ body.emit(assign(tmp, mul(add(mul(sub(mul(add(mul(sub(mul(add(mul(imm(-0.0121323213173444f),
+ tmp),
+ imm(0.0536813784310406f)),
+ tmp),
+ imm(0.1173503194786851f)),
+ tmp),
+ imm(0.1938924977115610f)),
+ tmp),
+ imm(0.3326756418091246f)),
+ tmp),
+ imm(0.9999793128310355f)),
+ x)));
+
+ /* range-reduction fixup */
+ body.emit(assign(tmp, add(tmp,
+ mul(b2f(greater(abs(y_over_x),
+ imm(1.0f, type->components()))),
+ add(mul(tmp,
+ imm(-2.0f)),
+ imm(M_PI_2f))))));
+
+ /* sign fixup */
+ body.emit(assign(res, mul(tmp, sign(y_over_x))));
+}
+
ir_function_signature *
builtin_builder::_atan(const glsl_type *type)
{
ir_variable *y_over_x = in_var(type, "y_over_x");
MAKE_SIG(type, always_available, 1, y_over_x);
- ir_variable *t = body.make_temp(type, "t");
- body.emit(assign(t, mul(y_over_x, rsq(add(mul(y_over_x, y_over_x),
- imm(1.0f))))));
-
- body.emit(ret(asin_expr(t)));
+ ir_variable *tmp = body.make_temp(type, "tmp");
+ do_atan(body, type, tmp, y_over_x);
+ body.emit(ret(tmp));
return sig;
}
@@ -4465,9 +4510,11 @@ builtin_builder::_image_prototype(const glsl_type *image_type,
sig->parameters.push_tail(in_var(glsl_type::int_type, "sample"));
/* Data arguments. */
- for (unsigned i = 0; i < num_arguments; ++i)
- sig->parameters.push_tail(in_var(data_type,
- ralloc_asprintf(NULL, "arg%d", i)));
+ for (unsigned i = 0; i < num_arguments; ++i) {
+ char *arg_name = ralloc_asprintf(NULL, "arg%d", i);
+ sig->parameters.push_tail(in_var(data_type, arg_name));
+ ralloc_free(arg_name);
+ }
/* Set the maximal set of qualifiers allowed for this image
* built-in. Function calls with arguments having fewer
diff --git a/mesalib/src/glsl/glsl_parser_extras.cpp b/mesalib/src/glsl/glsl_parser_extras.cpp
index cc7d2d746..79f849465 100644
--- a/mesalib/src/glsl/glsl_parser_extras.cpp
+++ b/mesalib/src/glsl/glsl_parser_extras.cpp
@@ -1613,6 +1613,7 @@ do_common_optimization(exec_list *ir, bool linked,
else
progress = do_constant_variable_unlinked(ir) || progress;
progress = do_constant_folding(ir) || progress;
+ progress = do_minmax_prune(ir) || progress;
progress = do_cse(ir) || progress;
progress = do_rebalance_tree(ir) || progress;
progress = do_algebraic(ir, native_integers, options) || progress;
diff --git a/mesalib/src/glsl/glsl_symbol_table.h b/mesalib/src/glsl/glsl_symbol_table.h
index db8863a20..21b02e919 100644..100755
--- a/mesalib/src/glsl/glsl_symbol_table.h
+++ b/mesalib/src/glsl/glsl_symbol_table.h
@@ -43,42 +43,13 @@ struct glsl_type;
* type safe and some symbol table invariants.
*/
struct glsl_symbol_table {
-private:
- static void
- _glsl_symbol_table_destructor (glsl_symbol_table *table)
- {
- table->~glsl_symbol_table();
- }
-
-public:
- /* Callers of this ralloc-based new need not call delete. It's
- * easier to just ralloc_free 'ctx' (or any of its ancestors). */
- static void* operator new(size_t size, void *ctx)
- {
- void *table;
-
- table = ralloc_size(ctx, size);
- assert(table != NULL);
-
- ralloc_set_destructor(table, (void (*)(void*)) _glsl_symbol_table_destructor);
-
- return table;
- }
-
- /* If the user *does* call delete, that's OK, we will just
- * ralloc_free in that case. Here, C++ will have already called the
- * destructor so tell ralloc not to do that again. */
+ DECLARE_RALLOC_CXX_OPERATORS(glsl_symbol_table)
static void operator delete(void *table, void *ctx)
{
ralloc_set_destructor(table, NULL);
ralloc_free(table);
}
- static void operator delete(void *table)
- {
- ralloc_set_destructor(table, NULL);
- ralloc_free(table);
- }
-
+
glsl_symbol_table();
~glsl_symbol_table();
diff --git a/mesalib/src/glsl/ir_optimization.h b/mesalib/src/glsl/ir_optimization.h
index 0c3a63831..e25857ac5 100644
--- a/mesalib/src/glsl/ir_optimization.h
+++ b/mesalib/src/glsl/ir_optimization.h
@@ -99,6 +99,7 @@ bool opt_flatten_nested_if_blocks(exec_list *instructions);
bool do_discard_simplification(exec_list *instructions);
bool lower_if_to_cond_assign(exec_list *instructions, unsigned max_depth = 0);
bool do_mat_op_to_vec(exec_list *instructions);
+bool do_minmax_prune(exec_list *instructions);
bool do_noop_swizzle(exec_list *instructions);
bool do_structure_splitting(exec_list *instructions);
bool do_swizzle_swizzle(exec_list *instructions);
diff --git a/mesalib/src/glsl/link_varyings.cpp b/mesalib/src/glsl/link_varyings.cpp
index a738e2f38..1866ab265 100644
--- a/mesalib/src/glsl/link_varyings.cpp
+++ b/mesalib/src/glsl/link_varyings.cpp
@@ -1456,7 +1456,22 @@ assign_varying_locations(struct gl_context *ctx,
if (var && var->data.mode == ir_var_shader_in &&
var->data.is_unmatched_generic_inout) {
- if (prog->Version <= 120) {
+ if (prog->IsES) {
+ /*
+ * On Page 91 (Page 97 of the PDF) of the GLSL ES 1.0 spec:
+ *
+ * If the vertex shader declares but doesn't write to a
+ * varying and the fragment shader declares and reads it,
+ * is this an error?
+ *
+ * RESOLUTION: No.
+ */
+ linker_warning(prog, "%s shader varying %s not written "
+ "by %s shader\n.",
+ _mesa_shader_stage_to_string(consumer->Stage),
+ var->name,
+ _mesa_shader_stage_to_string(producer->Stage));
+ } else if (prog->Version <= 120) {
/* On page 25 (page 31 of the PDF) of the GLSL 1.20 spec:
*
* Only those varying variables used (i.e. read) in
@@ -1469,7 +1484,6 @@ assign_varying_locations(struct gl_context *ctx,
* write the variable for the FS to read it. See
* "glsl1-varying read but not written" in piglit.
*/
-
linker_error(prog, "%s shader varying %s not written "
"by %s shader\n.",
_mesa_shader_stage_to_string(consumer->Stage),
diff --git a/mesalib/src/glsl/loop_analysis.h b/mesalib/src/glsl/loop_analysis.h
index 31be4f3cf..3b1971d7e 100644
--- a/mesalib/src/glsl/loop_analysis.h
+++ b/mesalib/src/glsl/loop_analysis.h
@@ -140,22 +140,7 @@ public:
hash_table_dtor(this->var_hash);
}
- static void* operator new(size_t size, void *ctx)
- {
- void *lvs = ralloc_size(ctx, size);
- assert(lvs != NULL);
-
- ralloc_set_destructor(lvs, (void (*)(void*)) destructor);
-
- return lvs;
- }
-
-private:
- static void
- destructor(loop_variable_state *lvs)
- {
- lvs->~loop_variable_state();
- }
+ DECLARE_RALLOC_CXX_OPERATORS(loop_variable_state)
};
diff --git a/mesalib/src/glsl/opt_minmax.cpp b/mesalib/src/glsl/opt_minmax.cpp
new file mode 100644
index 000000000..32fb2d7ea
--- /dev/null
+++ b/mesalib/src/glsl/opt_minmax.cpp
@@ -0,0 +1,475 @@
+/*
+ * Copyright © 2014 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.
+ */
+
+/**
+ * \file opt_minmax.cpp
+ *
+ * Drop operands from an expression tree of only min/max operations if they
+ * can be proven to not contribute to the final result.
+ *
+ * The algorithm is similar to alpha-beta pruning on a minmax search.
+ */
+
+#include "ir.h"
+#include "ir_visitor.h"
+#include "ir_rvalue_visitor.h"
+#include "ir_optimization.h"
+#include "ir_builder.h"
+#include "program/prog_instruction.h"
+#include "glsl_types.h"
+#include "main/macros.h"
+
+using namespace ir_builder;
+
+namespace {
+
+enum compare_components_result {
+ LESS,
+ LESS_OR_EQUAL,
+ EQUAL,
+ GREATER_OR_EQUAL,
+ GREATER,
+ MIXED
+};
+
+class minmax_range {
+public:
+ minmax_range(ir_constant *low = NULL, ir_constant *high = NULL)
+ {
+ this->low = low;
+ this->high = high;
+ }
+
+ /* low is the lower limit of the range, high is the higher limit. NULL on
+ * low means negative infinity (unlimited) and on high positive infinity
+ * (unlimited). Because of the two interpretations of the value NULL,
+ * arbitrary comparison between ir_constants is impossible.
+ */
+ ir_constant *low;
+ ir_constant *high;
+};
+
+class ir_minmax_visitor : public ir_rvalue_enter_visitor {
+public:
+ ir_minmax_visitor()
+ : progress(false)
+ {
+ }
+
+ ir_rvalue *prune_expression(ir_expression *expr, minmax_range baserange);
+
+ void handle_rvalue(ir_rvalue **rvalue);
+
+ bool progress;
+};
+
+/*
+ * Returns LESS if all vector components of `a' are strictly lower than of `b',
+ * GREATER if all vector components of `a' are strictly greater than of `b',
+ * MIXED if some vector components of `a' are strictly lower than of `b' while
+ * others are strictly greater, or EQUAL otherwise.
+ */
+static enum compare_components_result
+compare_components(ir_constant *a, ir_constant *b)
+{
+ assert(a != NULL);
+ assert(b != NULL);
+
+ assert(a->type->base_type == b->type->base_type);
+
+ unsigned a_inc = a->type->is_scalar() ? 0 : 1;
+ unsigned b_inc = b->type->is_scalar() ? 0 : 1;
+ unsigned components = MAX2(a->type->components(), b->type->components());
+
+ bool foundless = false;
+ bool foundgreater = false;
+ bool foundequal = false;
+
+ for (unsigned i = 0, c0 = 0, c1 = 0;
+ i < components;
+ c0 += a_inc, c1 += b_inc, ++i) {
+ switch (a->type->base_type) {
+ case GLSL_TYPE_UINT:
+ if (a->value.u[c0] < b->value.u[c1])
+ foundless = true;
+ else if (a->value.u[c0] > b->value.u[c1])
+ foundgreater = true;
+ else
+ foundequal = true;
+ break;
+ case GLSL_TYPE_INT:
+ if (a->value.i[c0] < b->value.i[c1])
+ foundless = true;
+ else if (a->value.i[c0] > b->value.i[c1])
+ foundgreater = true;
+ else
+ foundequal = true;
+ break;
+ case GLSL_TYPE_FLOAT:
+ if (a->value.f[c0] < b->value.f[c1])
+ foundless = true;
+ else if (a->value.f[c0] > b->value.f[c1])
+ foundgreater = true;
+ else
+ foundequal = true;
+ break;
+ default:
+ unreachable("not reached");
+ }
+ }
+
+ if (foundless && foundgreater) {
+ /* Some components are strictly lower, others are strictly greater */
+ return MIXED;
+ }
+
+ if (foundequal) {
+ /* It is not mixed, but it is not strictly lower or greater */
+ if (foundless)
+ return LESS_OR_EQUAL;
+ if (foundgreater)
+ return GREATER_OR_EQUAL;
+ return EQUAL;
+ }
+
+ /* All components are strictly lower or strictly greater */
+ return foundless ? LESS : GREATER;
+}
+
+static ir_constant *
+combine_constant(bool ismin, ir_constant *a, ir_constant *b)
+{
+ void *mem_ctx = ralloc_parent(a);
+ ir_constant *c = a->clone(mem_ctx, NULL);
+ for (unsigned i = 0; i < c->type->components(); i++) {
+ switch (c->type->base_type) {
+ case GLSL_TYPE_UINT:
+ if ((ismin && b->value.u[i] < c->value.u[i]) ||
+ (!ismin && b->value.u[i] > c->value.u[i]))
+ c->value.u[i] = b->value.u[i];
+ break;
+ case GLSL_TYPE_INT:
+ if ((ismin && b->value.i[i] < c->value.i[i]) ||
+ (!ismin && b->value.i[i] > c->value.i[i]))
+ c->value.i[i] = b->value.i[i];
+ break;
+ case GLSL_TYPE_FLOAT:
+ if ((ismin && b->value.f[i] < c->value.f[i]) ||
+ (!ismin && b->value.f[i] > c->value.f[i]))
+ c->value.f[i] = b->value.f[i];
+ break;
+ default:
+ assert(!"not reached");
+ }
+ }
+ return c;
+}
+
+static ir_constant *
+smaller_constant(ir_constant *a, ir_constant *b)
+{
+ assert(a != NULL);
+ assert(b != NULL);
+
+ enum compare_components_result ret = compare_components(a, b);
+ if (ret == MIXED)
+ return combine_constant(true, a, b);
+ else if (ret < EQUAL)
+ return a;
+ else
+ return b;
+}
+
+static ir_constant *
+larger_constant(ir_constant *a, ir_constant *b)
+{
+ assert(a != NULL);
+ assert(b != NULL);
+
+ enum compare_components_result ret = compare_components(a, b);
+ if (ret == MIXED)
+ return combine_constant(false, a, b);
+ else if (ret < EQUAL)
+ return b;
+ else
+ return a;
+}
+
+/* Combines two ranges by doing an element-wise min() / max() depending on the
+ * operation.
+ */
+static minmax_range
+combine_range(minmax_range r0, minmax_range r1, bool ismin)
+{
+ minmax_range ret;
+
+ if (!r0.low) {
+ ret.low = ismin ? r0.low : r1.low;
+ } else if (!r1.low) {
+ ret.low = ismin ? r1.low : r0.low;
+ } else {
+ ret.low = ismin ? smaller_constant(r0.low, r1.low) :
+ larger_constant(r0.low, r1.low);
+ }
+
+ if (!r0.high) {
+ ret.high = ismin ? r1.high : r0.high;
+ } else if (!r1.high) {
+ ret.high = ismin ? r0.high : r1.high;
+ } else {
+ ret.high = ismin ? smaller_constant(r0.high, r1.high) :
+ larger_constant(r0.high, r1.high);
+ }
+
+ return ret;
+}
+
+/* Returns a range so that lower limit is the larger of the two lower limits,
+ * and higher limit is the smaller of the two higher limits.
+ */
+static minmax_range
+range_intersection(minmax_range r0, minmax_range r1)
+{
+ minmax_range ret;
+
+ if (!r0.low)
+ ret.low = r1.low;
+ else if (!r1.low)
+ ret.low = r0.low;
+ else
+ ret.low = larger_constant(r0.low, r1.low);
+
+ if (!r0.high)
+ ret.high = r1.high;
+ else if (!r1.high)
+ ret.high = r0.high;
+ else
+ ret.high = smaller_constant(r0.high, r1.high);
+
+ return ret;
+}
+
+static minmax_range
+get_range(ir_rvalue *rval)
+{
+ ir_expression *expr = rval->as_expression();
+ if (expr && (expr->operation == ir_binop_min ||
+ expr->operation == ir_binop_max)) {
+ minmax_range r0 = get_range(expr->operands[0]);
+ minmax_range r1 = get_range(expr->operands[1]);
+ return combine_range(r0, r1, expr->operation == ir_binop_min);
+ }
+
+ ir_constant *c = rval->as_constant();
+ if (c) {
+ return minmax_range(c, c);
+ }
+
+ return minmax_range();
+}
+
+/**
+ * Prunes a min/max expression considering the base range of the parent
+ * min/max expression.
+ *
+ * @param baserange the range that the parents of this min/max expression
+ * in the min/max tree will clamp its value to.
+ */
+ir_rvalue *
+ir_minmax_visitor::prune_expression(ir_expression *expr, minmax_range baserange)
+{
+ assert(expr->operation == ir_binop_min ||
+ expr->operation == ir_binop_max);
+
+ bool ismin = expr->operation == ir_binop_min;
+ minmax_range limits[2];
+
+ /* Recurse to get the ranges for each of the subtrees of this
+ * expression. We need to do this as a separate step because we need to
+ * know the ranges of each of the subtrees before we prune either one.
+ * Consider something like this:
+ *
+ * max
+ * / \
+ * max max
+ * / \ / \
+ * 3 a b 2
+ *
+ * We would like to prune away the max on the bottom-right, but to do so
+ * we need to know the range of the expression on the left beforehand,
+ * and there's no guarantee that we will visit either subtree in a
+ * particular order.
+ */
+ for (unsigned i = 0; i < 2; ++i)
+ limits[i] = get_range(expr->operands[i]);
+
+ for (unsigned i = 0; i < 2; ++i) {
+ bool is_redundant = false;
+
+ enum compare_components_result cr = LESS;
+ if (ismin) {
+ /* If this operand will always be greater than the other one, it's
+ * redundant.
+ */
+ if (limits[i].low && limits[1 - i].high) {
+ cr = compare_components(limits[i].low, limits[1 - i].high);
+ if (cr >= EQUAL && cr != MIXED)
+ is_redundant = true;
+ }
+ /* If this operand is always greater than baserange, then even if
+ * it's smaller than the other one it'll get clamped, so it's
+ * redundant.
+ */
+ if (!is_redundant && limits[i].low && baserange.high) {
+ cr = compare_components(limits[i].low, baserange.high);
+ if (cr >= EQUAL && cr != MIXED)
+ is_redundant = true;
+ }
+ } else {
+ /* If this operand will always be lower than the other one, it's
+ * redundant.
+ */
+ if (limits[i].high && limits[1 - i].low) {
+ cr = compare_components(limits[i].high, limits[1 - i].low);
+ if (cr <= EQUAL)
+ is_redundant = true;
+ }
+ /* If this operand is always lower than baserange, then even if
+ * it's greater than the other one it'll get clamped, so it's
+ * redundant.
+ */
+ if (!is_redundant && limits[i].high && baserange.low) {
+ cr = compare_components(limits[i].high, baserange.low);
+ if (cr <= EQUAL)
+ is_redundant = true;
+ }
+ }
+
+ if (is_redundant) {
+ progress = true;
+
+ /* Recurse if necessary. */
+ ir_expression *op_expr = expr->operands[1 - i]->as_expression();
+ if (op_expr && (op_expr->operation == ir_binop_min ||
+ op_expr->operation == ir_binop_max)) {
+ return prune_expression(op_expr, baserange);
+ }
+
+ return expr->operands[1 - i];
+ } else if (cr == MIXED) {
+ /* If we have mixed vector operands, we can try to resolve the minmax
+ * expression by doing a component-wise minmax:
+ *
+ * min min
+ * / \ / \
+ * min a ===> [1,1] a
+ * / \
+ * [1,3] [3,1]
+ *
+ */
+ ir_constant *a = expr->operands[0]->as_constant();
+ ir_constant *b = expr->operands[1]->as_constant();
+ if (a && b)
+ return combine_constant(ismin, a, b);
+ }
+ }
+
+ /* Now recurse to operands giving them the proper baserange. The baserange
+ * to pass is the intersection of our baserange and the other operand's
+ * limit with one of the ranges unlimited. If we can't compute a valid
+ * intersection, we use the current baserange.
+ */
+ for (unsigned i = 0; i < 2; ++i) {
+ ir_expression *op_expr = expr->operands[i]->as_expression();
+ if (op_expr && (op_expr->operation == ir_binop_min ||
+ op_expr->operation == ir_binop_max)) {
+ /* We can only compute a new baserange for this operand if we managed
+ * to compute a valid range for the other operand.
+ */
+ if (ismin)
+ limits[1 - i].low = NULL;
+ else
+ limits[1 - i].high = NULL;
+ minmax_range base = range_intersection(limits[1 - i], baserange);
+ expr->operands[i] = prune_expression(op_expr, base);
+ }
+ }
+
+ /* If we got here we could not discard any of the operands of the minmax
+ * expression, but we can still try to resolve the expression if both
+ * operands are constant. We do this after the loop above, to make sure
+ * that if our operands are minmax expressions we have tried to prune them
+ * first (hopefully reducing them to constants).
+ */
+ ir_constant *a = expr->operands[0]->as_constant();
+ ir_constant *b = expr->operands[1]->as_constant();
+ if (a && b)
+ return combine_constant(ismin, a, b);
+
+ return expr;
+}
+
+static ir_rvalue *
+swizzle_if_required(ir_expression *expr, ir_rvalue *rval)
+{
+ if (expr->type->is_vector() && rval->type->is_scalar()) {
+ return swizzle(rval, SWIZZLE_XXXX, expr->type->vector_elements);
+ } else {
+ return rval;
+ }
+}
+
+void
+ir_minmax_visitor::handle_rvalue(ir_rvalue **rvalue)
+{
+ if (!*rvalue)
+ return;
+
+ ir_expression *expr = (*rvalue)->as_expression();
+ if (!expr || (expr->operation != ir_binop_min &&
+ expr->operation != ir_binop_max))
+ return;
+
+ ir_rvalue *new_rvalue = prune_expression(expr, minmax_range());
+ if (new_rvalue == *rvalue)
+ return;
+
+ /* If the expression type is a vector and the optimization leaves a scalar
+ * as the result, we need to turn it into a vector.
+ */
+ *rvalue = swizzle_if_required(expr, new_rvalue);
+
+ progress = true;
+}
+
+}
+
+bool
+do_minmax_prune(exec_list *instructions)
+{
+ ir_minmax_visitor v;
+
+ visit_list_elements(&v, instructions);
+
+ return v.progress;
+}