---
src/mesa/drivers/dri/i965/brw_fs.cpp | 18 +++++++++++++++++-
1 file changed, 17 insertions(+), 1 deletion(-)
diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp
b/src/mesa/drivers/dri/i965/brw_fs.cpp
index cf2f6ac..a677ea6 100644
--- a/src/mesa/drivers/dri/i965/brw_fs.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs.cpp
@@ -4747,7 +4747,6 @@ get_lowered_simd_width(const struct brw_device_info
*devinfo,
case BRW_OPCODE_SHR:
case BRW_OPCODE_SHL:
case BRW_OPCODE_ASR:
- case BRW_OPCODE_CMP:
case BRW_OPCODE_CMPN:
case BRW_OPCODE_CSEL:
case BRW_OPCODE_F32TO16:
@@ -4774,6 +4773,23 @@ get_lowered_simd_width(const struct brw_device_info
*devinfo,
case FS_OPCODE_PACK:
return get_fpu_lowered_simd_width(devinfo, inst);
+ case BRW_OPCODE_CMP: {
+ /* The Ivybridge/BayTrail WaCMPInstFlagDepClearedEarly workaround says
that
+ * when the destination is a GRF the dependency-clear bit on the flag
+ * register is cleared early.
+ *
+ * Suggested workarounds are to disable coissuing CMP instructions
+ * or to split CMP(16) instructions into two CMP(8) instructions.
+ *
+ * We choose to split into CMP(8) instructions since disabling
+ * coissuing would affect CMP instructions not otherwise affected by
+ * the errata.
+ */
+ const unsigned max_width = (devinfo->gen == 7 && !devinfo->is_haswell &&
+ !inst->dst.is_null() ? 8 : ~0);
+ return MIN2(max_width, get_fpu_lowered_simd_width(devinfo, inst));
+ }
+
case SHADER_OPCODE_RCP:
case SHADER_OPCODE_RSQ:
case SHADER_OPCODE_SQRT:
--
2.7.3
_______________________________________________
mesa-dev mailing list
mesa-dev@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/mesa-dev
