r600g: Fix special negative immediate constants when using ABS modifier.

Some constants (like 1.0 and 0.5) could be inlined as immediate inputs
without using their literal value. The r600_bytecode_special_constants()
function emulates the negative of these constants by using NEG modifier.

However some shaders define -1.0 constant and want to use it as 1.0.
They do so by using ABS modifier. But r600_bytecode_special_constants()
set NEG in addition to ABS. Since NEG modifier have priority over ABS one,
we get -|1.0| as result, instead of |1.0|.

The patch simply prevents the additional switching of NEG when ABS is set.

[According to Ivan Kalvachev, this bug was fond via
https://github.com/iXit/Mesa-3D/issues/126 and
https://github.com/iXit/Mesa-3D/issues/127]

Signed-off-by: Ivan Kalvachev <[email protected]>
Reviewed-by: Nicolai Hähnle <[email protected]>
CC: <[email protected]>

1 files changed, 1 insertions, 1 deletions

diff --git a/src/gallium/drivers/r600/r600_asm.h b/src/gallium/drivers/r600/r600_asm.h
index 7cf3a090908..d48ad1ebf01 100644
--- a/src/gallium/drivers/r600/r600_asm.h
+++ b/src/gallium/drivers/r600/r600_asm.h
@@ -255,7 +255,7 @@ int r600_bytecode_add_cfinst(struct r600_bytecode *bc,
 int r600_bytecode_add_alu_type(struct r600_bytecode *bc,
 		const struct r600_bytecode_alu *alu, unsigned type);
 void r600_bytecode_special_constants(uint32_t value,
-		unsigned *sel, unsigned *neg);
+		unsigned *sel, unsigned *neg, unsigned abs);
 void r600_bytecode_disasm(struct r600_bytecode *bc);
 void r600_bytecode_alu_read(struct r600_bytecode *bc,
 		struct r600_bytecode_alu *alu, uint32_t word0, uint32_t word1);