https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108984
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |hubicka at gcc dot gnu.org
--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
.optimized of LTRANS unit 60 has
# DEBUG BEGIN_STMT
# DEBUG D#456 => -align_bytes_448
# DEBUG D#453 => (long int) D#456
# DEBUG D#245 => 0
# DEBUG arg => D#453
# DEBUG INLINE_ENTRY gen_rtx_CONST_INT
# DEBUG D#246 => D#245
# DEBUG mode => D#246
_1005 = 64 - align_bytes_448;
_1045 = (long int) _1005;
_1046 = const_int_rtx[_1045];
# DEBUG mode => NULL
# DEBUG arg => NULL
_95 = this_target_rtl;
_96 = _95->x_global_rtl[0];
_97 = gen_and2_insn (_96, _1046);
and after IPA we see
# DEBUG BEGIN_STMT
_92 = -align_bytes_448;
_93 = (long int) _92;
# DEBUG D#245ptD.0 => 0
arg_1327 = _93;
# DEBUG arg => arg_1327
# DEBUG arg => arg_1327
# DEBUG INLINE_ENTRY gen_rtx_CONST_INT
# DEBUG D#246ptD.0 => D#245ptD.0
# DEBUG mode => D#246ptD.0
_1042 = arg_1327;
_1043 = (unsigned long) _1042;
_1044 = _1043 + 64;
if (_1044 <= 128)
goto <bb 59>; [51.12%]
else
goto <bb 60>; [48.88%]
<bb 59> [local count: 67075190]:
_1045 = _1042 + 64;
_1046 = const_int_rtx[_1045];
_1258 = _1046;
# DEBUG arg => NULL
# DEBUG mode => NULL
# DEBUG arg => NULL
_94 = _1258;
_95 = this_target_rtl;
_96 = _95->x_global_rtl[0];
# USE = anything
# CLB = anything
_97 = gen_and2_insn (_96, _94);
# USE = anything
# CLB = anything
insn_472 = emit_insn (_97);
# DEBUG insn => insn_472
# DEBUG BEGIN_STMT
# DEBUG BEGIN_STMT
# DEBUG _rtx => insn_472
# DEBUG BEGIN_STMT
_98 = insn_472->code;
_99 = _98 + 65528;
switch (_98) <default: <L12> [0.00%], case 8 ... 11: <L13> [100.00%], case
13: <L13> [100.00%], case 25: <L13> [100.00%]>
<bb 60> [local count: 64136059]:
_1047 = const_int_htab;
_1048 = (unsigned int) _1042;
# USE = anything
# CLB = anything
__builtin_unreachable ();
so it looks like the else path materialized to be unreachable for some
reason. Before IPA we have
_92 = -align_bytes_448;
_93 = (long int) _92;
_94 = gen_rtx_CONST_INT (0, _93);
IPA CP knows
callsite ix86_expand_prologue/1286343 -> gen_rtx_CONST_INT/244924 :
param 0: CONST: 0
value: 0x0, mask: 0x0
Unknown VR
param 1: UNKNOWN
value: 0x0, mask:
0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
VR [-536870911, -5]
callsite ix86_expand_prologue/1286343 -> gen_rtx_CONST_INT/244924 :
param 0: CONST: 0
value: 0x0, mask: 0x0
Unknown VR
param 1: UNKNOWN
value: 0x0, mask:
0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
VR [-536870911, 0]
and it at least creates a constprop clone for VOIDmode.
Considering gen_rtx_CONST_INT.constprop/2274667 with 38 size
to be inlined into ix86_expand_prologue/1286343 in unknown:-1
Estimated badness is -0.000000, frequency 0.12.
Badness calculation for ix86_expand_prologue/1286343 ->
gen_rtx_CONST_INT.constprop/2274667
size growth 2, time 4.533600 unspec 7.533600 IPA hints: cross_module
-0.000000: guessed profile. frequency 0.122200, count -1 caller count -1
time saved 1.955200 overall growth 62692 (current) 39603 (original) 104883
(compensated)
Adjusted by hints -0.000000
Parm map: -5 -5
I'm somewhat lost as to where to look for why that unreachable () is created.
It looks like the inliner redirects things this way.
