[Mesa-dev] [PATCH 3/4] i965/fs: Reject copy propagation into SEL if not min/max.

[Matt Turner]

We shouldn't ever see a SEL with conditional mod other than GE (for max)
or L (for min), but we might see one with predication and no conditional
mod.

total instructions in shared programs: 8241806 -> 8241902 (0.00%)
instructions in affected programs: 13284 -> 13380 (0.72%)
HURT: 62

total cycles in shared programs: 84165104 -> 84166244 (0.00%)
cycles in affected programs: 75364 -> 76504 (1.51%)
helped: 10
HURT: 34

Fixes generated code in at least Sanctum 2, Borderlands 2, Goat
Simulator, and XCOM: Enemy Unknown.
---
 src/mesa/drivers/dri/i965/brw_fs_copy_propagation.cpp  | 4 +++-
 src/mesa/drivers/dri/i965/test_fs_copy_propagation.cpp | 9 +++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/src/mesa/drivers/dri/i965/brw_fs_copy_propagation.cpp b/src/mesa/drivers/dri/i965/brw_fs_copy_propagation.cpp
index 53cd111..cb11739 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_copy_propagation.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_copy_propagation.cpp
@@ -431,7 +431,9 @@ fs_visitor::try_copy_propagate(fs_inst *inst, int arg, acp_entry *entry)
    if (entry->saturate) {
       switch(inst->opcode) {
       case BRW_OPCODE_SEL:
-         if (inst->src[1].file != IMM ||
+         if ((inst->conditional_mod != BRW_CONDITIONAL_GE &&
+              inst->conditional_mod != BRW_CONDITIONAL_L) ||
+             inst->src[1].file != IMM ||
              inst->src[1].f < 0.0 ||
              inst->src[1].f > 1.0) {
             return false;
diff --git a/src/mesa/drivers/dri/i965/test_fs_copy_propagation.cpp b/src/mesa/drivers/dri/i965/test_fs_copy_propagation.cpp
index 80e71b4..37736ec 100644
--- a/src/mesa/drivers/dri/i965/test_fs_copy_propagation.cpp
+++ b/src/mesa/drivers/dri/i965/test_fs_copy_propagation.cpp
@@ -163,6 +163,15 @@ TEST_F(copy_propagation_test, maxmax_sat_imm)
       { BRW_CONDITIONAL_L   , -1.5f, false },
       { BRW_CONDITIONAL_GE  ,  1.5f, false },
       { BRW_CONDITIONAL_L   ,  1.5f, false },
+
+      { BRW_CONDITIONAL_NONE, 0.5f, false },
+      { BRW_CONDITIONAL_Z   , 0.5f, false },
+      { BRW_CONDITIONAL_NZ  , 0.5f, false },
+      { BRW_CONDITIONAL_G   , 0.5f, false },
+      { BRW_CONDITIONAL_LE  , 0.5f, false },
+      { BRW_CONDITIONAL_R   , 0.5f, false },
+      { BRW_CONDITIONAL_O   , 0.5f, false },
+      { BRW_CONDITIONAL_U   , 0.5f, false },
    };
 
    for (unsigned i = 0; i < sizeof(test) / sizeof(test[0]); i++) {
-- 
2.7.3