diff options
| author | Kenneth Graunke <[email protected]> | 2014-10-15 18:57:07 -0700 |
|---|---|---|
| committer | Kenneth Graunke <[email protected]> | 2014-10-21 21:14:03 -0700 |
| commit | 6dc6e6e0d979aa666e2934ae40477195e4d37ceb (patch) | |
| tree | 6eb446c75b75e282379a1856ce555bc64f7f3007 /src/mesa/drivers | |
| parent | f5c3f095b97dc5d8997ca448ffffbca67b3db4d5 (diff) | |
i965/vec4: Generate better code for ir_triop_csel.
Previously, we generated an extra CMP instruction:
cmp.ge.f0(8) g6<1>D g1<0,4,1>F 0F
cmp.nz.f0(8) null g6<4,4,1>D 0D
(+f0) sel(8) g5<1>F g1.4<0,4,1>F g2<0,4,1>F
The first operand is always a boolean, and we want to predicate the SEL
on that. Rather than producing a boolean value and comparing it against
zero, we can just produce a condition code in the flag register.
Now we generate:
cmp.ge.f0(8) null g1<0,4,1>F 0F
(+f0) sel(8) g5<1>F g1.4<0,4,1>F g2<0,4,1>F
No difference in shader-db.
v2: Remember to delete the old code (thanks Matt).
Signed-off-by: Kenneth Graunke <[email protected]>
Reviewed-by: Matt Turner <[email protected]>
Diffstat (limited to 'src/mesa/drivers')
| -rw-r--r-- | src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp index d0587cd5f62..b46879b7beb 100644 --- a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp +++ b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp @@ -1277,6 +1277,20 @@ vec4_visitor::visit(ir_expression *ir) dst_reg result_dst(this, ir->type); src_reg result_src(result_dst); + if (ir->operation == ir_triop_csel) { + ir->operands[1]->accept(this); + op[1] = this->result; + ir->operands[2]->accept(this); + op[2] = this->result; + + enum brw_predicate predicate; + emit_bool_to_cond_code(ir->operands[0], &predicate); + inst = emit(BRW_OPCODE_SEL, result_dst, op[1], op[2]); + inst->predicate = predicate; + this->result = result_src; + return; + } + for (operand = 0; operand < ir->get_num_operands(); operand++) { this->result.file = BAD_FILE; ir->operands[operand]->accept(this); @@ -1780,9 +1794,7 @@ vec4_visitor::visit(ir_expression *ir) break; case ir_triop_csel: - emit(CMP(dst_null_d(), op[0], src_reg(0), BRW_CONDITIONAL_NZ)); - inst = emit(BRW_OPCODE_SEL, result_dst, op[1], op[2]); - inst->predicate = BRW_PREDICATE_NORMAL; + unreachable("already handled above"); break; case ir_triop_bfi: |