[Mesa-dev] [PATCH 3/5] r600: use ieee version of rcp

sroland at vmware.com sroland at vmware.com
Thu Nov 9 19:00:47 UTC 2017


From: Roland Scheidegger <sroland at vmware.com>

r600 used the clamped version for rcp, whereas both evergreen and cayman
used the ieee version. I don't know why that discrepancy exists (it does so
since day 1) but there does not seem to be a valid reason for this, so make
it consistent. This seems now safer than before the previous commit (using
the dx10 clamp bit).
Note that rsq still uses clamped version (as before even though the table
may have suggested otherwise for evergreen) for r600/eg, but not for cayman.
Will be changed separately for better regression tracking...
---
 src/gallium/drivers/r600/r600_shader.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/src/gallium/drivers/r600/r600_shader.c b/src/gallium/drivers/r600/r600_shader.c
index e9054c4fbb..2ece2210a6 100644
--- a/src/gallium/drivers/r600/r600_shader.c
+++ b/src/gallium/drivers/r600/r600_shader.c
@@ -8830,11 +8830,7 @@ static const struct r600_shader_tgsi_instruction r600_shader_tgsi_instruction[]
 	[TGSI_OPCODE_MOV]	= { ALU_OP1_MOV, tgsi_op2},
 	[TGSI_OPCODE_LIT]	= { ALU_OP0_NOP, tgsi_lit},
 
-	/* XXX:
-	 * For state trackers other than OpenGL, we'll want to use
-	 * _RECIP_IEEE instead.
-	 */
-	[TGSI_OPCODE_RCP]	= { ALU_OP1_RECIP_CLAMPED, tgsi_trans_srcx_replicate},
+	[TGSI_OPCODE_RCP]	= { ALU_OP1_RECIP_IEEE, tgsi_trans_srcx_replicate},
 
 	[TGSI_OPCODE_RSQ]	= { ALU_OP0_NOP, tgsi_rsq},
 	[TGSI_OPCODE_EXP]	= { ALU_OP0_NOP, tgsi_exp},
@@ -9035,7 +9031,7 @@ static const struct r600_shader_tgsi_instruction eg_shader_tgsi_instruction[] =
 	[TGSI_OPCODE_MOV]	= { ALU_OP1_MOV, tgsi_op2},
 	[TGSI_OPCODE_LIT]	= { ALU_OP0_NOP, tgsi_lit},
 	[TGSI_OPCODE_RCP]	= { ALU_OP1_RECIP_IEEE, tgsi_trans_srcx_replicate},
-	[TGSI_OPCODE_RSQ]	= { ALU_OP1_RECIPSQRT_IEEE, tgsi_rsq},
+	[TGSI_OPCODE_RSQ]	= { ALU_OP0_NOP, tgsi_rsq},
 	[TGSI_OPCODE_EXP]	= { ALU_OP0_NOP, tgsi_exp},
 	[TGSI_OPCODE_LOG]	= { ALU_OP0_NOP, tgsi_log},
 	[TGSI_OPCODE_MUL]	= { ALU_OP2_MUL_IEEE, tgsi_op2},
-- 
2.12.3



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