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Hexagon (target/hexagon) Remove gen_log_predicated_reg_write[_pair]

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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>
This commit is contained in:
Taylor Simpson 2023-03-06 18:58:26 -08:00
parent 1a442c0931
commit e28b77a6b4
8 changed files with 110 additions and 152 deletions
Download patch file Download diff file Expand all files Collapse all files

6
target/hexagon/gen_tcg.h
View file

@ -332,8 +332,6 @@
tcg_gen_movi_tl(EA, 0); \
PRED; \
CHECK_NOSHUF_PRED(GET_EA, SIZE, LSB); \
PRED_LOAD_CANCEL(LSB, EA); \
tcg_gen_movi_tl(RdV, 0); \
tcg_gen_brcondi_tl(TCG_COND_EQ, LSB, 0, label); \
fLOAD(1, SIZE, SIGN, EA, RdV); \
gen_set_label(label); \
@ -391,8 +389,6 @@
tcg_gen_movi_tl(EA, 0); \
PRED; \
CHECK_NOSHUF_PRED(GET_EA, 8, LSB); \
PRED_LOAD_CANCEL(LSB, EA); \
tcg_gen_movi_i64(RddV, 0); \
tcg_gen_brcondi_tl(TCG_COND_EQ, LSB, 0, label); \
fLOAD(1, 8, u, EA, RddV); \
gen_set_label(label); \
@ -504,7 +500,7 @@
*/
#define fGEN_TCG_SL2_return(SHORTCODE) \
do { \
TCGv_i64 RddV = tcg_temp_new_i64(); \
TCGv_i64 RddV = get_result_gpr_pair(ctx, HEX_REG_FP); \
gen_return(ctx, RddV, hex_gpr[HEX_REG_FP]); \
gen_log_reg_write_pair(HEX_REG_FP, RddV); \
} while (0)