tree e26e230e5932be0876de614ef737e084d1603743
parent 1a442c09310de23d7cab4c5efedba607c2672d44
author Taylor Simpson <tsimpson@quicinc.com> 1678157906 -0800
committer Taylor Simpson <tsimpson@quicinc.com> 1678164432 -0800

Hexagon (target/hexagon) Remove gen_log_predicated_reg_write[_pair]

We assign the instruction destination register to hex_new_value[num]
instead of a TCG temp that gets copied back to hex_new_value[num].

We introduce new functions get_result_gpr[_pair] to facilitate getting
the proper destination register.

Since we preload hex_new_value for predicated instructions, we don't
need the check for slot_cancelled.  So, we call gen_log_reg_write instead.

We update the helper function generation and gen_tcg.h to maintain the
disable-hexagon-idef-parser configuration.

Here is a simple example of the differences in the TCG code generated:

IN:
0x00400094:  0xf900c102 {       if (P0) R2 = and(R0,R1) }

BEFORE
 ---- 00400094
 mov_i32 slot_cancelled,$0x0
 mov_i32 new_r2,r2
 mov_i32 loc2,$0x0
 and_i32 tmp0,p0,$0x1
 brcond_i32 tmp0,$0x0,eq,$L1
 and_i32 tmp0,r0,r1
 mov_i32 loc2,tmp0
 br $L2
 set_label $L1
 or_i32 slot_cancelled,slot_cancelled,$0x8
 set_label $L2
 and_i32 tmp0,slot_cancelled,$0x8
 movcond_i32 new_r2,tmp0,$0x0,loc2,new_r2,eq
 mov_i32 r2,new_r2

AFTER
 ---- 00400094
 mov_i32 slot_cancelled,$0x0
 mov_i32 new_r2,r2
 and_i32 tmp0,p0,$0x1
 brcond_i32 tmp0,$0x0,eq,$L1
 and_i32 tmp0,r0,r1
 mov_i32 new_r2,tmp0
 br $L2
 set_label $L1
 or_i32 slot_cancelled,slot_cancelled,$0x8
 set_label $L2
 mov_i32 r2,new_r2

We'll remove the unnecessary manipulation of slot_cancelled in a
subsequent patch.

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20230307025828.1612809-13-tsimpson@quicinc.com>