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* [Bug target/112970] New: LoongArch: Suboptimal code when the address and the value of an array element are both used
@ 2023-12-11 20:53 xry111 at gcc dot gnu.org
2023-12-12 6:54 ` [Bug target/112970] " xry111 at gcc dot gnu.org
2023-12-12 6:55 ` xry111 at gcc dot gnu.org
0 siblings, 2 replies; 3+ messages in thread
From: xry111 at gcc dot gnu.org @ 2023-12-11 20:53 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112970
Bug ID: 112970
Summary: LoongArch: Suboptimal code when the address and the
value of an array element are both used
Product: gcc
Version: 14.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: xry111 at gcc dot gnu.org
Target Milestone: ---
int d[2];
struct r { int *p, v; };
struct r test() { return (struct r){&d[1], d[1]}; }
is compiled to:
la.local $r12,.LANCHOR0
ld.wu $r5,$r12,4
la.local $r4,.LANCHOR0+4
But it's better to be:
la.local $r4,.LANCHOR0+4
ld.wu $r5,$r4,0
^ permalink raw reply [flat|nested] 3+ messages in thread* [Bug target/112970] LoongArch: Suboptimal code when the address and the value of an array element are both used
2023-12-11 20:53 [Bug target/112970] New: LoongArch: Suboptimal code when the address and the value of an array element are both used xry111 at gcc dot gnu.org
@ 2023-12-12 6:54 ` xry111 at gcc dot gnu.org
2023-12-12 6:55 ` xry111 at gcc dot gnu.org
1 sibling, 0 replies; 3+ messages in thread
From: xry111 at gcc dot gnu.org @ 2023-12-12 6:54 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112970
--- Comment #1 from Xi Ruoyao <xry111 at gcc dot gnu.org> ---
With -mexplicit-relocs=auto the generated code is sub-optimal as well:
pcalau12i $r12,%pc_hi20(.LANCHOR0)
addi.d $r12,$r12,%pc_lo12(.LANCHOR0)
ld.wu $r5,$r12,4
addi.d $r4,$r12,4
^ permalink raw reply [flat|nested] 3+ messages in thread* [Bug target/112970] LoongArch: Suboptimal code when the address and the value of an array element are both used
2023-12-11 20:53 [Bug target/112970] New: LoongArch: Suboptimal code when the address and the value of an array element are both used xry111 at gcc dot gnu.org
2023-12-12 6:54 ` [Bug target/112970] " xry111 at gcc dot gnu.org
@ 2023-12-12 6:55 ` xry111 at gcc dot gnu.org
1 sibling, 0 replies; 3+ messages in thread
From: xry111 at gcc dot gnu.org @ 2023-12-12 6:55 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112970
--- Comment #2 from Xi Ruoyao <xry111 at gcc dot gnu.org> ---
(In reply to Xi Ruoyao from comment #1)
> With -mexplicit-relocs=auto the generated code is sub-optimal as well:
I mean "always", not "auto".
> pcalau12i $r12,%pc_hi20(.LANCHOR0)
> addi.d $r12,$r12,%pc_lo12(.LANCHOR0)
> ld.wu $r5,$r12,4
> addi.d $r4,$r12,4
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2023-12-12 6:55 UTC | newest]
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2023-12-11 20:53 [Bug target/112970] New: LoongArch: Suboptimal code when the address and the value of an array element are both used xry111 at gcc dot gnu.org
2023-12-12 6:54 ` [Bug target/112970] " xry111 at gcc dot gnu.org
2023-12-12 6:55 ` xry111 at gcc dot gnu.org
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