https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87238
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
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Keywords| |ra
--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Note I had to change the testcase to be using size 128.
But this is interesting, IRA was able to figure the memset return value:
(call_insn 14 13 17 2 (parallel [
(set (reg:DI 0 x0)
(call (mem:DI (symbol_ref:DI ("memcpy") [flags 0x41]
<function_decl 0x7efee90fd200 __builtin_memcpy>) [0 __builtin_memcpy S8 A8])
(const_int 0 [0])))
(unspec:DI [
(const_int 0 [0])
] UNSPEC_CALLEE_ABI)
(clobber (reg:DI 30 x30))
]) "/app/example.cpp":10:16 47 {*call_value_insn}
(expr_list:REG_RETURNED (reg/f:DI 95)
(expr_list:REG_DEAD (reg:DI 2 x2)
(expr_list:REG_DEAD (reg:DI 1 x1)
(expr_list:REG_UNUSED (reg:DI 0 x0)
(expr_list:REG_CALL_DECL (symbol_ref:DI ("memcpy") [flags
0x41] <function_decl 0x7efee90fd200 __builtin_memcpy>)
(expr_list:REG_EH_REGION (const_int 0 [0])
(nil)))))))
(expr_list (clobber (reg:DI 17 x17))
(expr_list (clobber (reg:DI 16 x16))
(expr_list:DI (set (reg:DI 0 x0)
(reg:DI 0 x0))
(expr_list:DI (use (reg:DI 0 x0))
(expr_list:DI (use (reg:DI 1 x1))
(expr_list:DI (use (reg:DI 2 x2))
(nil))))))))
(insn 17 14 18 2 (set (reg:DI 0 x0)
(reg/f:DI 95)) "/app/example.cpp":10:16 53 {*movdi_aarch64}
(expr_list:REG_DEAD (reg/f:DI 95)
(expr_list:REG_EQUAL (plus:DI (reg/f:DI 64 sfp)
(const_int -512 [0xfffffffffffffe00]))
(nil))))
But not actually use it.
REG_RETURNED (reg/f:DI 95)
Instead if used the REG_EQUAL ....
