From: Jason Ekstrand Date: Mon, 28 Mar 2016 18:47:27 +0000 (-0700) Subject: i965/peephole_ffma: Only match a mul+add if none of the ops are exact X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=5d9afb65a60f022af0daddbb21bc57bb2c830606;p=mesa.git i965/peephole_ffma: Only match a mul+add if none of the ops are exact --- diff --git a/src/mesa/drivers/dri/i965/brw_nir_opt_peephole_ffma.c b/src/mesa/drivers/dri/i965/brw_nir_opt_peephole_ffma.c index 6e8b1f99505..22ff2e3c9f8 100644 --- a/src/mesa/drivers/dri/i965/brw_nir_opt_peephole_ffma.c +++ b/src/mesa/drivers/dri/i965/brw_nir_opt_peephole_ffma.c @@ -84,6 +84,17 @@ get_mul_for_src(nir_alu_src *src, int num_components, return NULL; nir_alu_instr *alu = nir_instr_as_alu(instr); + + /* We want to bail if any of the other ALU operations involved is labled + * exact. One reason for this is that, while the value that is changing is + * actually the result of the add and not the multiply, the intention of + * the user when they specify an exact multiply is that they want *that* + * value and what they don't care about is the add. Another reason is that + * SPIR-V explicitly requires this behaviour. + */ + if (alu->exact) + return NULL; + switch (alu->op) { case nir_op_imov: case nir_op_fmov: