diff options
Diffstat (limited to 'mesalib/src/glsl/lower_instructions.cpp')
| -rw-r--r-- | mesalib/src/glsl/lower_instructions.cpp | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/mesalib/src/glsl/lower_instructions.cpp b/mesalib/src/glsl/lower_instructions.cpp index a8ef7654e..1ce7b7c9d 100644 --- a/mesalib/src/glsl/lower_instructions.cpp +++ b/mesalib/src/glsl/lower_instructions.cpp @@ -37,6 +37,7 @@ * - POW_TO_EXP2 * - LOG_TO_LOG2 * - MOD_TO_FRACT + * - LRP_TO_ARITH * * SUB_TO_ADD_NEG: * --------------- @@ -79,13 +80,20 @@ * Many GPUs don't have a MOD instruction (945 and 965 included), and * if we have to break it down like this anyway, it gives an * opportunity to do things like constant fold the (1.0 / op1) easily. + * + * LRP_TO_ARITH: + * ------------- + * Converts ir_triop_lrp to (op0 * (1.0f - op2)) + (op1 * op2). */ #include "main/core.h" /* for M_LOG2E */ #include "glsl_types.h" #include "ir.h" +#include "ir_builder.h" #include "ir_optimization.h" +using namespace ir_builder; + class lower_instructions_visitor : public ir_hierarchical_visitor { public: lower_instructions_visitor(unsigned lower) @@ -105,6 +113,7 @@ private: void exp_to_exp2(ir_expression *); void pow_to_exp2(ir_expression *); void log_to_log2(ir_expression *); + void lrp_to_arith(ir_expression *); }; /** @@ -268,6 +277,27 @@ lower_instructions_visitor::mod_to_fract(ir_expression *ir) this->progress = true; } +void +lower_instructions_visitor::lrp_to_arith(ir_expression *ir) +{ + /* (lrp x y a) -> x*(1-a) + y*a */ + + /* Save op2 */ + ir_variable *temp = new(ir) ir_variable(ir->operands[2]->type, "lrp_factor", + ir_var_temporary); + this->base_ir->insert_before(temp); + this->base_ir->insert_before(assign(temp, ir->operands[2])); + + ir_constant *one = new(ir) ir_constant(1.0f); + + ir->operation = ir_binop_add; + ir->operands[0] = mul(ir->operands[0], sub(one, temp)); + ir->operands[1] = mul(ir->operands[1], temp); + ir->operands[2] = NULL; + + this->progress = true; +} + ir_visitor_status lower_instructions_visitor::visit_leave(ir_expression *ir) { @@ -304,6 +334,11 @@ lower_instructions_visitor::visit_leave(ir_expression *ir) pow_to_exp2(ir); break; + case ir_triop_lrp: + if (lowering(LRP_TO_ARITH)) + lrp_to_arith(ir); + break; + default: return visit_continue; } |