https://gcc.gnu.org/bugzilla/show_bug.cgi?id=18041
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |segher at gcc dot gnu.org
--- Comment #9 from Richard Biener <rguenth at gcc dot gnu.org> ---
Looks like combine doesn't want
(insn 11 10 13 2 (parallel [
(set (reg:QI 91)
(ior:QI (mem/c:QI (plus:SI (reg/f:SI 16 argp)
(const_int 4 [0x4])) [4 x+0 S1 A32])
(reg:QI 90 [ *b_3(D) ])))
(clobber (reg:CC 17 flags))
]) "t.c":12:11 429 {*iorqi_1}
(expr_list:REG_UNUSED (reg:CC 17 flags)
(nil)))
for a combination (on x86_64 with -m32).
(insn 13 11 15 2 (parallel [
(set (reg:QI 93)
(and:QI (reg:QI 91)
(const_int 1 [0x1])))
(clobber (reg:CC 17 flags))
]) "t.c":12:11 396 {*andqi_1}
(expr_list:REG_UNUSED (reg:CC 17 flags)
(expr_list:REG_DEAD (reg:QI 91)
(nil))))
(insn 15 13 16 2 (parallel [
(set (reg:QI 95)
(and:QI (reg:QI 90 [ *b_3(D) ])
(const_int -2 [0xfffffffffffffffe])))
(clobber (reg:CC 17 flags))
]) "t.c":12:11 396 {*andqi_1}
(expr_list:REG_DEAD (reg:QI 90 [ *b_3(D) ])
(expr_list:REG_UNUSED (reg:CC 17 flags)
(nil))))
(insn 16 15 17 2 (parallel [
(set (reg:QI 96)
(ior:QI (reg:QI 95)
(reg:QI 93)))
(clobber (reg:CC 17 flags))
]) "t.c":12:11 429 {*iorqi_1}
(expr_list:REG_DEAD (reg:QI 95)
(expr_list:REG_DEAD (reg:QI 93)
(expr_list:REG_UNUSED (reg:CC 17 flags)
(nil)))))
Trying 11, 15, 13 -> 16:
11: {r91:QI=[argp:SI+0x4]|r90:QI;clobber flags:CC;}
REG_UNUSED flags:CC
15: {r95:QI=r90:QI&0xfffffffffffffffe;clobber flags:CC;}
REG_DEAD r90:QI
REG_UNUSED flags:CC
13: {r93:QI=r91:QI&0x1;clobber flags:CC;}
REG_UNUSED flags:CC
REG_DEAD r91:QI
16: {r96:QI=r95:QI|r93:QI;clobber flags:CC;}
REG_DEAD r95:QI
REG_DEAD r93:QI
REG_UNUSED flags:CC
Failed to match this instruction:
(parallel [
(set (reg:QI 96)
(ior:QI (and:QI (mem/c:QI (plus:SI (reg/f:SI 16 argp)
(const_int 4 [0x4])) [4 x+0 S1 A32])
(const_int 1 [0x1]))
(reg:QI 90 [ *b_3(D) ])))
(clobber (reg:CC 17 flags))
])
Failed to match this instruction:
(set (reg:QI 96)
(ior:QI (and:QI (mem/c:QI (plus:SI (reg/f:SI 16 argp)
(const_int 4 [0x4])) [4 x+0 S1 A32])
(const_int 1 [0x1]))
(reg:QI 90 [ *b_3(D) ])))
Failed to match this instruction:
(set (reg:QI 95)
(and:QI (mem/c:QI (plus:SI (reg/f:SI 16 argp)
(const_int 4 [0x4])) [4 x+0 S1 A32])
(const_int 1 [0x1])))
looks like it doesn't try to "factor" out the load?
