summaryrefslogtreecommitdiffstats
path: root/src/glsl
diff options
context:
space:
mode:
authorAbdiel Janulgue <abdiel.janulgue@linux.intel.com>2014-06-12 14:59:30 -0700
committerAbdiel Janulgue <abdiel.janulgue@linux.intel.com>2014-08-31 21:04:08 +0300
commit8935c129372c02c56005463bb8b7182e0aeefd65 (patch)
treea0c42a3af90c22a72860e8d3402d649684207beb /src/glsl
parent4c0ccfc5b39bf69ef90145e5ccf4cea04d9a8a73 (diff)
glsl: Add a pass to lower ir_unop_saturate to clamp(x, 0, 1)
Signed-off-by: Abdiel Janulgue <abdiel.janulgue@linux.intel.com> Reviewed-by: Matt Turner <mattst88@gmail.com> Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Diffstat (limited to 'src/glsl')
-rw-r--r--src/glsl/ir_optimization.h1
-rw-r--r--src/glsl/lower_instructions.cpp29
2 files changed, 30 insertions, 0 deletions
diff --git a/src/glsl/ir_optimization.h b/src/glsl/ir_optimization.h
index b83c2259234..1c6f72b544f 100644
--- a/src/glsl/ir_optimization.h
+++ b/src/glsl/ir_optimization.h
@@ -40,6 +40,7 @@
#define LDEXP_TO_ARITH 0x100
#define CARRY_TO_ARITH 0x200
#define BORROW_TO_ARITH 0x400
+#define SAT_TO_CLAMP 0x800
/**
* \see class lower_packing_builtins_visitor
diff --git a/src/glsl/lower_instructions.cpp b/src/glsl/lower_instructions.cpp
index 176070c8781..684285350d0 100644
--- a/src/glsl/lower_instructions.cpp
+++ b/src/glsl/lower_instructions.cpp
@@ -41,6 +41,7 @@
* - BITFIELD_INSERT_TO_BFM_BFI
* - CARRY_TO_ARITH
* - BORROW_TO_ARITH
+ * - SAT_TO_CLAMP
*
* SUB_TO_ADD_NEG:
* ---------------
@@ -104,6 +105,10 @@
* ----------------
* Converts ir_borrow into (x < y).
*
+ * SAT_TO_CLAMP:
+ * -------------
+ * Converts ir_unop_saturate into min(max(x, 0.0), 1.0)
+ *
*/
#include "main/core.h" /* for M_LOG2E */
@@ -139,6 +144,7 @@ private:
void ldexp_to_arith(ir_expression *);
void carry_to_arith(ir_expression *);
void borrow_to_arith(ir_expression *);
+ void sat_to_clamp(ir_expression *);
};
} /* anonymous namespace */
@@ -484,6 +490,24 @@ lower_instructions_visitor::borrow_to_arith(ir_expression *ir)
this->progress = true;
}
+void
+lower_instructions_visitor::sat_to_clamp(ir_expression *ir)
+{
+ /* Translates
+ * ir_unop_saturate x
+ * into
+ * ir_binop_min (ir_binop_max(x, 0.0), 1.0)
+ */
+
+ ir->operation = ir_binop_min;
+ ir->operands[0] = new(ir) ir_expression(ir_binop_max, ir->operands[0]->type,
+ ir->operands[0],
+ new(ir) ir_constant(0.0f));
+ ir->operands[1] = new(ir) ir_constant(1.0f);
+
+ this->progress = true;
+}
+
ir_visitor_status
lower_instructions_visitor::visit_leave(ir_expression *ir)
{
@@ -540,6 +564,11 @@ lower_instructions_visitor::visit_leave(ir_expression *ir)
borrow_to_arith(ir);
break;
+ case ir_unop_saturate:
+ if (lowering(SAT_TO_CLAMP))
+ sat_to_clamp(ir);
+ break;
+
default:
return visit_continue;
}