From 020b0055e7a085a6a8c961ad12ce94e58606a1ae Mon Sep 17 00:00:00 2001 From: Ian Romanick Date: Fri, 9 Mar 2018 13:45:01 -0800 Subject: [PATCH] i965/fs: Propagate conditional modifiers from compares to adds MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The math inside the add and the cmp in this instruction sequence is the same. We can utilize this to eliminate the compare. add(8) g5<1>F g2<8,8,1>F g64.5<0,1,0>F { align1 1Q compacted }; cmp.z.f0(8) null<1>F g2<8,8,1>F -g64.5<0,1,0>F { align1 1Q switch }; (-f0) sel(8) g8<1>F (abs)g5<8,8,1>F 3e-37F { align1 1Q }; This is reduced to: add.z.f0(8) g5<1>F g2<8,8,1>F g64.5<0,1,0>F { align1 1Q compacted }; (-f0) sel(8) g8<1>F (abs)g5<8,8,1>F 3e-37F { align1 1Q }; This optimization pass could do even better. The nature of converting vectorized code from the GLSL front end to scalar code in NIR results in sequences like: add(8) g7<1>F g4<8,8,1>F g64.5<0,1,0>F { align1 1Q compacted }; add(8) g6<1>F g3<8,8,1>F g64.5<0,1,0>F { align1 1Q compacted }; add(8) g5<1>F g2<8,8,1>F g64.5<0,1,0>F { align1 1Q compacted }; cmp.z.f0(8) null<1>F g2<8,8,1>F -g64.5<0,1,0>F { align1 1Q switch }; (-f0) sel(8) g8<1>F (abs)g5<8,8,1>F 3e-37F { align1 1Q }; cmp.z.f0(8) null<1>F g3<8,8,1>F -g64.5<0,1,0>F { align1 1Q switch }; (-f0) sel(8) g10<1>F (abs)g6<8,8,1>F 3e-37F { align1 1Q }; cmp.z.f0(8) null<1>F g4<8,8,1>F -g64.5<0,1,0>F { align1 1Q switch }; (-f0) sel(8) g12<1>F (abs)g7<8,8,1>F 3e-37F { align1 1Q }; In this sequence, only the first cmp.z is removed. With different scheduling, all 3 could get removed. Skylake total instructions in shared programs: 14407009 -> 14400173 (-0.05%) instructions in affected programs: 1307274 -> 1300438 (-0.52%) helped: 4880 HURT: 0 helped stats (abs) min: 1 max: 33 x̄: 1.40 x̃: 1 helped stats (rel) min: 0.03% max: 8.70% x̄: 0.70% x̃: 0.52% 95% mean confidence interval for instructions value: -1.45 -1.35 95% mean confidence interval for instructions %-change: -0.72% -0.69% Instructions are helped. total cycles in shared programs: 532943169 -> 532923528 (<.01%) cycles in affected programs: 14065798 -> 14046157 (-0.14%) helped: 2703 HURT: 339 helped stats (abs) min: 1 max: 1062 x̄: 12.27 x̃: 2 helped stats (rel) min: <.01% max: 28.72% x̄: 0.38% x̃: 0.21% HURT stats (abs) min: 1 max: 739 x̄: 39.86 x̃: 12 HURT stats (rel) min: 0.02% max: 27.69% x̄: 1.38% x̃: 0.41% 95% mean confidence interval for cycles value: -8.66 -4.26 95% mean confidence interval for cycles %-change: -0.24% -0.14% Cycles are helped. LOST: 0 GAINED: 1 Broadwell total instructions in shared programs: 14719636 -> 14712949 (-0.05%) instructions in affected programs: 1288188 -> 1281501 (-0.52%) helped: 4845 HURT: 0 helped stats (abs) min: 1 max: 33 x̄: 1.38 x̃: 1 helped stats (rel) min: 0.03% max: 8.00% x̄: 0.70% x̃: 0.52% 95% mean confidence interval for instructions value: -1.43 -1.33 95% mean confidence interval for instructions %-change: -0.72% -0.68% Instructions are helped. total cycles in shared programs: 559599253 -> 559581699 (<.01%) cycles in affected programs: 13315565 -> 13298011 (-0.13%) helped: 2600 HURT: 269 helped stats (abs) min: 1 max: 2128 x̄: 12.24 x̃: 2 helped stats (rel) min: <.01% max: 23.95% x̄: 0.41% x̃: 0.20% HURT stats (abs) min: 1 max: 790 x̄: 53.07 x̃: 20 HURT stats (rel) min: 0.02% max: 15.96% x̄: 1.55% x̃: 0.75% 95% mean confidence interval for cycles value: -8.47 -3.77 95% mean confidence interval for cycles %-change: -0.27% -0.18% Cycles are helped. LOST: 0 GAINED: 8 Haswell total instructions in shared programs: 12978609 -> 12973483 (-0.04%) instructions in affected programs: 932921 -> 927795 (-0.55%) helped: 3480 HURT: 0 helped stats (abs) min: 1 max: 33 x̄: 1.47 x̃: 1 helped stats (rel) min: 0.03% max: 7.84% x̄: 0.78% x̃: 0.58% 95% mean confidence interval for instructions value: -1.53 -1.42 95% mean confidence interval for instructions %-change: -0.80% -0.75% Instructions are helped. total cycles in shared programs: 410270788 -> 410250531 (<.01%) cycles in affected programs: 10986161 -> 10965904 (-0.18%) helped: 2087 HURT: 254 helped stats (abs) min: 1 max: 2672 x̄: 14.63 x̃: 4 helped stats (rel) min: <.01% max: 39.61% x̄: 0.42% x̃: 0.21% HURT stats (abs) min: 1 max: 519 x̄: 40.49 x̃: 16 HURT stats (rel) min: 0.01% max: 12.83% x̄: 1.20% x̃: 0.47% 95% mean confidence interval for cycles value: -12.82 -4.49 95% mean confidence interval for cycles %-change: -0.31% -0.18% Cycles are helped. LOST: 0 GAINED: 5 Ivy Bridge total instructions in shared programs: 11686082 -> 11681548 (-0.04%) instructions in affected programs: 937696 -> 933162 (-0.48%) helped: 3150 HURT: 0 helped stats (abs) min: 1 max: 33 x̄: 1.44 x̃: 1 helped stats (rel) min: 0.03% max: 7.84% x̄: 0.69% x̃: 0.49% 95% mean confidence interval for instructions value: -1.49 -1.38 95% mean confidence interval for instructions %-change: -0.71% -0.67% Instructions are helped. total cycles in shared programs: 257514962 -> 257492471 (<.01%) cycles in affected programs: 11524149 -> 11501658 (-0.20%) helped: 1970 HURT: 239 helped stats (abs) min: 1 max: 3525 x̄: 17.48 x̃: 3 helped stats (rel) min: <.01% max: 49.60% x̄: 0.46% x̃: 0.17% HURT stats (abs) min: 1 max: 1358 x̄: 50.00 x̃: 15 HURT stats (rel) min: 0.02% max: 59.88% x̄: 1.84% x̃: 0.65% 95% mean confidence interval for cycles value: -17.01 -3.35 95% mean confidence interval for cycles %-change: -0.33% -0.08% Cycles are helped. LOST: 9 GAINED: 1 Sandy Bridge total instructions in shared programs: 10432841 -> 10429893 (-0.03%) instructions in affected programs: 685071 -> 682123 (-0.43%) helped: 2453 HURT: 0 helped stats (abs) min: 1 max: 9 x̄: 1.20 x̃: 1 helped stats (rel) min: 0.02% max: 7.55% x̄: 0.64% x̃: 0.46% 95% mean confidence interval for instructions value: -1.23 -1.17 95% mean confidence interval for instructions %-change: -0.67% -0.62% Instructions are helped. total cycles in shared programs: 146133660 -> 146134195 (<.01%) cycles in affected programs: 3991634 -> 3992169 (0.01%) helped: 1237 HURT: 153 helped stats (abs) min: 1 max: 2853 x̄: 6.93 x̃: 2 helped stats (rel) min: <.01% max: 29.00% x̄: 0.24% x̃: 0.14% HURT stats (abs) min: 1 max: 1740 x̄: 59.56 x̃: 12 HURT stats (rel) min: 0.03% max: 78.98% x̄: 1.96% x̃: 0.42% 95% mean confidence interval for cycles value: -5.13 5.90 95% mean confidence interval for cycles %-change: -0.17% 0.16% Inconclusive result (value mean confidence interval includes 0). LOST: 0 GAINED: 1 GM45 and Iron Lake had similar results (GM45 shown): total instructions in shared programs: 4800332 -> 4798380 (-0.04%) instructions in affected programs: 565995 -> 564043 (-0.34%) helped: 1451 HURT: 0 helped stats (abs) min: 1 max: 20 x̄: 1.35 x̃: 1 helped stats (rel) min: 0.05% max: 5.26% x̄: 0.47% x̃: 0.31% 95% mean confidence interval for instructions value: -1.40 -1.29 95% mean confidence interval for instructions %-change: -0.50% -0.45% Instructions are helped. total cycles in shared programs: 122032318 -> 122027798 (<.01%) cycles in affected programs: 8334868 -> 8330348 (-0.05%) helped: 1029 HURT: 1 helped stats (abs) min: 2 max: 40 x̄: 4.43 x̃: 2 helped stats (rel) min: <.01% max: 1.83% x̄: 0.09% x̃: 0.04% HURT stats (abs) min: 38 max: 38 x̄: 38.00 x̃: 38 HURT stats (rel) min: 0.25% max: 0.25% x̄: 0.25% x̃: 0.25% 95% mean confidence interval for cycles value: -4.70 -4.08 95% mean confidence interval for cycles %-change: -0.09% -0.08% Cycles are helped. Signed-off-by: Ian Romanick Reviewed-by: Alejandro Piñeiro Reviewed-by: Matt Turner --- .../compiler/brw_fs_cmod_propagation.cpp | 70 +++- .../compiler/test_fs_cmod_propagation.cpp | 335 ++++++++++++++++++ 2 files changed, 400 insertions(+), 5 deletions(-) diff --git a/src/intel/compiler/brw_fs_cmod_propagation.cpp b/src/intel/compiler/brw_fs_cmod_propagation.cpp index b995a51d3c3..462e51d504e 100644 --- a/src/intel/compiler/brw_fs_cmod_propagation.cpp +++ b/src/intel/compiler/brw_fs_cmod_propagation.cpp @@ -63,8 +63,14 @@ opt_cmod_propagation_local(const gen_device_info *devinfo, bblock_t *block) inst->predicate != BRW_PREDICATE_NONE || !inst->dst.is_null() || (inst->src[0].file != VGRF && inst->src[0].file != ATTR && - inst->src[0].file != UNIFORM) || - inst->src[0].abs) + inst->src[0].file != UNIFORM)) + continue; + + /* An ABS source modifier can only be handled when processing a compare + * with a value other than zero. + */ + if (inst->src[0].abs && + (inst->opcode != BRW_OPCODE_CMP || inst->src[1].is_zero())) continue; /* Only an AND.NZ can be propagated. Many AND.Z instructions are @@ -80,15 +86,68 @@ opt_cmod_propagation_local(const gen_device_info *devinfo, bblock_t *block) !inst->src[0].negate)) continue; - if (inst->opcode == BRW_OPCODE_CMP && !inst->src[1].is_zero()) - continue; - if (inst->opcode == BRW_OPCODE_MOV && inst->conditional_mod != BRW_CONDITIONAL_NZ) continue; bool read_flag = false; foreach_inst_in_block_reverse_starting_from(fs_inst, scan_inst, inst) { + /* A CMP with a second source of zero can match with anything. A CMP + * with a second source that is not zero can only match with an ADD + * instruction. + */ + if (inst->opcode == BRW_OPCODE_CMP && !inst->src[1].is_zero()) { + bool negate; + + if (scan_inst->opcode != BRW_OPCODE_ADD) + goto not_match; + + /* A CMP is basically a subtraction. The result of the + * subtraction must be the same as the result of the addition. + * This means that one of the operands must be negated. So (a + + * b) vs (a == -b) or (a + -b) vs (a == b). + */ + if ((inst->src[0].equals(scan_inst->src[0]) && + inst->src[1].negative_equals(scan_inst->src[1])) || + (inst->src[0].equals(scan_inst->src[1]) && + inst->src[1].negative_equals(scan_inst->src[0]))) { + negate = false; + } else if ((inst->src[0].negative_equals(scan_inst->src[0]) && + inst->src[1].equals(scan_inst->src[1])) || + (inst->src[0].negative_equals(scan_inst->src[1]) && + inst->src[1].equals(scan_inst->src[0]))) { + negate = true; + } else { + goto not_match; + } + + if (scan_inst->is_partial_write() || + scan_inst->exec_size != inst->exec_size) + goto not_match; + + /* From the Sky Lake PRM Vol. 7 "Assigning Conditional Mods": + * + * * Note that the [post condition signal] bits generated at + * the output of a compute are before the .sat. + * + * So we don't have to bail if scan_inst has saturate. + */ + + /* Otherwise, try propagating the conditional. */ + const enum brw_conditional_mod cond = + negate ? brw_swap_cmod(inst->conditional_mod) + : inst->conditional_mod; + + if (scan_inst->can_do_cmod() && + ((!read_flag && scan_inst->conditional_mod == BRW_CONDITIONAL_NONE) || + scan_inst->conditional_mod == cond)) { + scan_inst->conditional_mod = cond; + inst->remove(block); + progress = true; + } + break; + } + if (regions_overlap(scan_inst->dst, scan_inst->size_written, inst->src[0], inst->size_read(0))) { if (scan_inst->is_partial_write() || @@ -183,6 +242,7 @@ opt_cmod_propagation_local(const gen_device_info *devinfo, bblock_t *block) break; } + not_match: if (scan_inst->flags_written()) break; diff --git a/src/intel/compiler/test_fs_cmod_propagation.cpp b/src/intel/compiler/test_fs_cmod_propagation.cpp index a97e374f74e..659fbb2d1bc 100644 --- a/src/intel/compiler/test_fs_cmod_propagation.cpp +++ b/src/intel/compiler/test_fs_cmod_propagation.cpp @@ -554,3 +554,338 @@ TEST_F(cmod_propagation_test, andz_one) EXPECT_EQ(BRW_OPCODE_AND, instruction(block0, 1)->opcode); EXPECT_EQ(BRW_CONDITIONAL_EQ, instruction(block0, 1)->conditional_mod); } + +TEST_F(cmod_propagation_test, add_not_merge_with_compare) +{ + const fs_builder &bld = v->bld; + fs_reg dest = v->vgrf(glsl_type::float_type); + fs_reg src0 = v->vgrf(glsl_type::float_type); + fs_reg src1 = v->vgrf(glsl_type::float_type); + bld.ADD(dest, src0, src1); + bld.CMP(bld.null_reg_f(), src0, src1, BRW_CONDITIONAL_L); + + /* The addition and the implicit subtraction in the compare do not compute + * related values. + * + * = Before = + * 0: add(8) dest:F src0:F src1:F + * 1: cmp.l.f0(8) null:F src0:F src1:F + * + * = After = + * (no changes) + */ + v->calculate_cfg(); + bblock_t *block0 = v->cfg->blocks[0]; + + EXPECT_EQ(0, block0->start_ip); + EXPECT_EQ(1, block0->end_ip); + + EXPECT_FALSE(cmod_propagation(v)); + EXPECT_EQ(0, block0->start_ip); + EXPECT_EQ(1, block0->end_ip); + EXPECT_EQ(BRW_OPCODE_ADD, instruction(block0, 0)->opcode); + EXPECT_EQ(BRW_CONDITIONAL_NONE, instruction(block0, 0)->conditional_mod); + EXPECT_EQ(BRW_OPCODE_CMP, instruction(block0, 1)->opcode); + EXPECT_EQ(BRW_CONDITIONAL_L, instruction(block0, 1)->conditional_mod); +} + +TEST_F(cmod_propagation_test, subtract_merge_with_compare) +{ + const fs_builder &bld = v->bld; + fs_reg dest = v->vgrf(glsl_type::float_type); + fs_reg src0 = v->vgrf(glsl_type::float_type); + fs_reg src1 = v->vgrf(glsl_type::float_type); + bld.ADD(dest, src0, negate(src1)); + bld.CMP(bld.null_reg_f(), src0, src1, BRW_CONDITIONAL_L); + + /* = Before = + * 0: add(8) dest:F src0:F -src1:F + * 1: cmp.l.f0(8) null:F src0:F src1:F + * + * = After = + * 0: add.l.f0(8) dest:F src0:F -src1:F + */ + v->calculate_cfg(); + bblock_t *block0 = v->cfg->blocks[0]; + + EXPECT_EQ(0, block0->start_ip); + EXPECT_EQ(1, block0->end_ip); + + EXPECT_TRUE(cmod_propagation(v)); + EXPECT_EQ(0, block0->start_ip); + EXPECT_EQ(0, block0->end_ip); + EXPECT_EQ(BRW_OPCODE_ADD, instruction(block0, 0)->opcode); + EXPECT_EQ(BRW_CONDITIONAL_L, instruction(block0, 0)->conditional_mod); +} + +TEST_F(cmod_propagation_test, subtract_immediate_merge_with_compare) +{ + const fs_builder &bld = v->bld; + fs_reg dest = v->vgrf(glsl_type::float_type); + fs_reg src0 = v->vgrf(glsl_type::float_type); + fs_reg one(brw_imm_f(1.0f)); + fs_reg negative_one(brw_imm_f(-1.0f)); + + bld.ADD(dest, src0, negative_one); + bld.CMP(bld.null_reg_f(), src0, one, BRW_CONDITIONAL_NZ); + + /* = Before = + * 0: add(8) dest:F src0:F -1.0f + * 1: cmp.nz.f0(8) null:F src0:F 1.0f + * + * = After = + * 0: add.nz.f0(8) dest:F src0:F -1.0f + */ + v->calculate_cfg(); + bblock_t *block0 = v->cfg->blocks[0]; + + EXPECT_EQ(0, block0->start_ip); + EXPECT_EQ(1, block0->end_ip); + + EXPECT_TRUE(cmod_propagation(v)); + EXPECT_EQ(0, block0->start_ip); + EXPECT_EQ(0, block0->end_ip); + EXPECT_EQ(BRW_OPCODE_ADD, instruction(block0, 0)->opcode); + EXPECT_EQ(BRW_CONDITIONAL_NZ, instruction(block0, 0)->conditional_mod); +} + +TEST_F(cmod_propagation_test, subtract_merge_with_compare_intervening_add) +{ + const fs_builder &bld = v->bld; + fs_reg dest0 = v->vgrf(glsl_type::float_type); + fs_reg dest1 = v->vgrf(glsl_type::float_type); + fs_reg src0 = v->vgrf(glsl_type::float_type); + fs_reg src1 = v->vgrf(glsl_type::float_type); + bld.ADD(dest0, src0, negate(src1)); + bld.ADD(dest1, src0, src1); + bld.CMP(bld.null_reg_f(), src0, src1, BRW_CONDITIONAL_L); + + /* = Before = + * 0: add(8) dest0:F src0:F -src1:F + * 1: add(8) dest1:F src0:F src1:F + * 2: cmp.l.f0(8) null:F src0:F src1:F + * + * = After = + * 0: add.l.f0(8) dest0:F src0:F -src1:F + * 1: add(8) dest1:F src0:F src1:F + */ + v->calculate_cfg(); + bblock_t *block0 = v->cfg->blocks[0]; + + EXPECT_EQ(0, block0->start_ip); + EXPECT_EQ(2, block0->end_ip); + + EXPECT_TRUE(cmod_propagation(v)); + EXPECT_EQ(0, block0->start_ip); + EXPECT_EQ(1, block0->end_ip); + EXPECT_EQ(BRW_OPCODE_ADD, instruction(block0, 0)->opcode); + EXPECT_EQ(BRW_CONDITIONAL_L, instruction(block0, 0)->conditional_mod); + EXPECT_EQ(BRW_OPCODE_ADD, instruction(block0, 1)->opcode); + EXPECT_EQ(BRW_CONDITIONAL_NONE, instruction(block0, 1)->conditional_mod); +} + +TEST_F(cmod_propagation_test, subtract_not_merge_with_compare_intervening_partial_write) +{ + const fs_builder &bld = v->bld; + fs_reg dest0 = v->vgrf(glsl_type::float_type); + fs_reg dest1 = v->vgrf(glsl_type::float_type); + fs_reg src0 = v->vgrf(glsl_type::float_type); + fs_reg src1 = v->vgrf(glsl_type::float_type); + bld.ADD(dest0, src0, negate(src1)); + set_predicate(BRW_PREDICATE_NORMAL, bld.ADD(dest1, src0, negate(src1))); + bld.CMP(bld.null_reg_f(), src0, src1, BRW_CONDITIONAL_L); + + /* = Before = + * 0: add(8) dest0:F src0:F -src1:F + * 1: (+f0) add(8) dest1:F src0:F -src1:F + * 2: cmp.l.f0(8) null:F src0:F src1:F + * + * = After = + * (no changes) + */ + v->calculate_cfg(); + bblock_t *block0 = v->cfg->blocks[0]; + + EXPECT_EQ(0, block0->start_ip); + EXPECT_EQ(2, block0->end_ip); + + EXPECT_FALSE(cmod_propagation(v)); + EXPECT_EQ(0, block0->start_ip); + EXPECT_EQ(2, block0->end_ip); + EXPECT_EQ(BRW_OPCODE_ADD, instruction(block0, 0)->opcode); + EXPECT_EQ(BRW_CONDITIONAL_NONE, instruction(block0, 0)->conditional_mod); + EXPECT_EQ(BRW_OPCODE_ADD, instruction(block0, 1)->opcode); + EXPECT_EQ(BRW_CONDITIONAL_NONE, instruction(block0, 1)->conditional_mod); + EXPECT_EQ(BRW_OPCODE_CMP, instruction(block0, 2)->opcode); + EXPECT_EQ(BRW_CONDITIONAL_L, instruction(block0, 2)->conditional_mod); +} + +TEST_F(cmod_propagation_test, subtract_not_merge_with_compare_intervening_add) +{ + const fs_builder &bld = v->bld; + fs_reg dest0 = v->vgrf(glsl_type::float_type); + fs_reg dest1 = v->vgrf(glsl_type::float_type); + fs_reg src0 = v->vgrf(glsl_type::float_type); + fs_reg src1 = v->vgrf(glsl_type::float_type); + bld.ADD(dest0, src0, negate(src1)); + set_condmod(BRW_CONDITIONAL_EQ, bld.ADD(dest1, src0, src1)); + bld.CMP(bld.null_reg_f(), src0, src1, BRW_CONDITIONAL_L); + + /* = Before = + * 0: add(8) dest0:F src0:F -src1:F + * 1: add.z.f0(8) dest1:F src0:F src1:F + * 2: cmp.l.f0(8) null:F src0:F src1:F + * + * = After = + * (no changes) + */ + v->calculate_cfg(); + bblock_t *block0 = v->cfg->blocks[0]; + + EXPECT_EQ(0, block0->start_ip); + EXPECT_EQ(2, block0->end_ip); + + EXPECT_FALSE(cmod_propagation(v)); + EXPECT_EQ(0, block0->start_ip); + EXPECT_EQ(2, block0->end_ip); + EXPECT_EQ(BRW_OPCODE_ADD, instruction(block0, 0)->opcode); + EXPECT_EQ(BRW_CONDITIONAL_NONE, instruction(block0, 0)->conditional_mod); + EXPECT_EQ(BRW_OPCODE_ADD, instruction(block0, 1)->opcode); + EXPECT_EQ(BRW_CONDITIONAL_EQ, instruction(block0, 1)->conditional_mod); + EXPECT_EQ(BRW_OPCODE_CMP, instruction(block0, 2)->opcode); + EXPECT_EQ(BRW_CONDITIONAL_L, instruction(block0, 2)->conditional_mod); +} + +TEST_F(cmod_propagation_test, add_merge_with_compare) +{ + const fs_builder &bld = v->bld; + fs_reg dest = v->vgrf(glsl_type::float_type); + fs_reg src0 = v->vgrf(glsl_type::float_type); + fs_reg src1 = v->vgrf(glsl_type::float_type); + bld.ADD(dest, src0, src1); + bld.CMP(bld.null_reg_f(), src0, negate(src1), BRW_CONDITIONAL_L); + + /* = Before = + * 0: add(8) dest:F src0:F src1:F + * 1: cmp.l.f0(8) null:F src0:F -src1:F + * + * = After = + * 0: add.l.f0(8) dest:F src0:F src1:F + */ + v->calculate_cfg(); + bblock_t *block0 = v->cfg->blocks[0]; + + EXPECT_EQ(0, block0->start_ip); + EXPECT_EQ(1, block0->end_ip); + + EXPECT_TRUE(cmod_propagation(v)); + EXPECT_EQ(0, block0->start_ip); + EXPECT_EQ(0, block0->end_ip); + EXPECT_EQ(BRW_OPCODE_ADD, instruction(block0, 0)->opcode); + EXPECT_EQ(BRW_CONDITIONAL_L, instruction(block0, 0)->conditional_mod); +} + +TEST_F(cmod_propagation_test, negative_subtract_merge_with_compare) +{ + const fs_builder &bld = v->bld; + fs_reg dest = v->vgrf(glsl_type::float_type); + fs_reg src0 = v->vgrf(glsl_type::float_type); + fs_reg src1 = v->vgrf(glsl_type::float_type); + bld.ADD(dest, src1, negate(src0)); + bld.CMP(bld.null_reg_f(), src0, src1, BRW_CONDITIONAL_L); + + /* The result of the subtract is the negatiion of the result of the + * implicit subtract in the compare, so the condition must change. + * + * = Before = + * 0: add(8) dest:F src1:F -src0:F + * 1: cmp.l.f0(8) null:F src0:F src1:F + * + * = After = + * 0: add.g.f0(8) dest:F src0:F -src1:F + */ + v->calculate_cfg(); + bblock_t *block0 = v->cfg->blocks[0]; + + EXPECT_EQ(0, block0->start_ip); + EXPECT_EQ(1, block0->end_ip); + + EXPECT_TRUE(cmod_propagation(v)); + EXPECT_EQ(0, block0->start_ip); + EXPECT_EQ(0, block0->end_ip); + EXPECT_EQ(BRW_OPCODE_ADD, instruction(block0, 0)->opcode); + EXPECT_EQ(BRW_CONDITIONAL_G, instruction(block0, 0)->conditional_mod); +} + +TEST_F(cmod_propagation_test, subtract_delete_compare) +{ + const fs_builder &bld = v->bld; + fs_reg dest = v->vgrf(glsl_type::float_type); + fs_reg dest1 = v->vgrf(glsl_type::float_type); + fs_reg src0 = v->vgrf(glsl_type::float_type); + fs_reg src1 = v->vgrf(glsl_type::float_type); + fs_reg src2 = v->vgrf(glsl_type::float_type); + + set_condmod(BRW_CONDITIONAL_L, bld.ADD(dest, src0, negate(src1))); + set_predicate(BRW_PREDICATE_NORMAL, bld.MOV(dest1, src2)); + bld.CMP(bld.null_reg_f(), src0, src1, BRW_CONDITIONAL_L); + + /* = Before = + * 0: add.l.f0(8) dest0:F src0:F -src1:F + * 1: (+f0) mov(0) dest1:F src2:F + * 2: cmp.l.f0(8) null:F src0:F src1:F + * + * = After = + * 0: add.l.f0(8) dest:F src0:F -src1:F + * 1: (+f0) mov(0) dest1:F src2:F + */ + v->calculate_cfg(); + bblock_t *block0 = v->cfg->blocks[0]; + + EXPECT_EQ(0, block0->start_ip); + EXPECT_EQ(2, block0->end_ip); + + EXPECT_TRUE(cmod_propagation(v)); + EXPECT_EQ(0, block0->start_ip); + EXPECT_EQ(1, block0->end_ip); + EXPECT_EQ(BRW_OPCODE_ADD, instruction(block0, 0)->opcode); + EXPECT_EQ(BRW_CONDITIONAL_L, instruction(block0, 0)->conditional_mod); + EXPECT_EQ(BRW_OPCODE_MOV, instruction(block0, 1)->opcode); + EXPECT_EQ(BRW_PREDICATE_NORMAL, instruction(block0, 1)->predicate); +} + +TEST_F(cmod_propagation_test, subtract_delete_compare_derp) +{ + const fs_builder &bld = v->bld; + fs_reg dest0 = v->vgrf(glsl_type::float_type); + fs_reg dest1 = v->vgrf(glsl_type::float_type); + fs_reg src0 = v->vgrf(glsl_type::float_type); + fs_reg src1 = v->vgrf(glsl_type::float_type); + + set_condmod(BRW_CONDITIONAL_L, bld.ADD(dest0, src0, negate(src1))); + set_predicate(BRW_PREDICATE_NORMAL, bld.ADD(dest1, negate(src0), src1)); + bld.CMP(bld.null_reg_f(), src0, src1, BRW_CONDITIONAL_L); + + /* = Before = + * 0: add.l.f0(8) dest0:F src0:F -src1:F + * 1: (+f0) add(0) dest1:F -src0:F src1:F + * 2: cmp.l.f0(8) null:F src0:F src1:F + * + * = After = + * 0: add.l.f0(8) dest0:F src0:F -src1:F + * 1: (+f0) add(0) dest1:F -src0:F src1:F + */ + v->calculate_cfg(); + bblock_t *block0 = v->cfg->blocks[0]; + + EXPECT_EQ(0, block0->start_ip); + EXPECT_EQ(2, block0->end_ip); + + EXPECT_TRUE(cmod_propagation(v)); + EXPECT_EQ(0, block0->start_ip); + EXPECT_EQ(1, block0->end_ip); + EXPECT_EQ(BRW_OPCODE_ADD, instruction(block0, 0)->opcode); + EXPECT_EQ(BRW_CONDITIONAL_L, instruction(block0, 0)->conditional_mod); + EXPECT_EQ(BRW_OPCODE_ADD, instruction(block0, 1)->opcode); + EXPECT_EQ(BRW_PREDICATE_NORMAL, instruction(block0, 1)->predicate); +} -- 2.30.2