https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103252
--- Comment #11 from Hongtao.liu <crazylht at gmail dot com> --- > Why cprop_hardreg can't handle this? cprop_hardreg only prop hard register, not memory. (insn 86 85 227 15 (set (reg:SI 68 k0 [132]) (mem/u/c:SI (plus:SI (reg:SI 3 bx [82]) (const:SI (unspec:SI [ (symbol_ref:SI ("__libc_tsd_CTYPE_B") [flags 0x60] <var_decl 0x7f6668cf2b40 __libc_tsd_CTYPE_B>) ] UNSPEC_GOTNTPOFF))) [7 S4 A8])) "est.c":81:67 75 {*movsi_internal} (expr_list:REG_EQUIV (mem/u/c:SI (plus:SI (reg:SI 3 bx [82]) (const:SI (unspec:SI [ (symbol_ref:SI ("__libc_tsd_CTYPE_B") [flags 0x60] <var_decl 0x7f6668cf2b40 __libc_tsd_CTYPE_B>) ] UNSPEC_GOTNTPOFF))) [7 S4 A8]) (nil))) (insn 227 86 202 15 (set (reg:SI 2 cx [132]) (reg:SI 68 k0 [132])) test.c":81:67 75 {*movsi_internal} (expr_list:REG_DEAD (reg:SI 68 k0 [132]) (nil))) (insn 202 227 88 15 (set (reg/f:SI 68 k0 [orig:131 __libc_tsd_CTYPE_B ] [131]) (mem/f/c:SI (reg:SI 2 cx [132]) [4 __libc_tsd_CTYPE_B+0 S4 A32 AS2])) "test.c":81:67 75 {*movsi_internal} (expr_list:REG_DEAD (reg:SI 2 cx [132]) (nil))) (note 88 202 89 15 NOTE_INSN_DELETED) (note 89 88 228 15 NOTE_INSN_DELETED) (insn 228 89 203 15 (set (reg/f:SI 2 cx [orig:131 __libc_tsd_CTYPE_B ] [131]) (reg/f:SI 68 k0 [orig:131 __libc_tsd_CTYPE_B ] [131])) "test.c":81:43 75 {*movsi_internal} (expr_list:REG_DEAD (reg/f:SI 68 k0 [orig:131 __libc_tsd_CTYPE_B ] [131]) (nil)))