[Bug tree-optimization/100512] [12 Regression] ICE during GIMPLE pass: cddce in mark_operand_necessary, at tree-ssa-dce.c:173 (under -O2 to -Os) since r12-623-g1416a1434c43de0b
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100512 Martin Liška changed: What|Removed |Added Status|NEW |RESOLVED Resolution|--- |FIXED --- Comment #9 from Martin Liška --- I guess it's fixed now.
[Bug tree-optimization/100512] [12 Regression] ICE during GIMPLE pass: cddce in mark_operand_necessary, at tree-ssa-dce.c:173 (under -O2 to -Os) since r12-623-g1416a1434c43de0b
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100512 --- Comment #8 from CVS Commits --- The master branch has been updated by Andrew Macleod : https://gcc.gnu.org/g:3f476de7fd274f619a0b04c2e2f7077ee8ab17a5 commit r12-852-g3f476de7fd274f619a0b04c2e2f7077ee8ab17a5 Author: Andrew MacLeod Date: Mon May 17 15:53:39 2021 -0400 Once a range becomes constant, make it invariant. Once a range is forced to a constant globally, simply make it invariant. Unify this with the code which makes non-zero pointer ranges invariant. gcc/ PR tree-optimization/100512 * gimple-range-cache.cc (ranger_cache::set_global_range): Mark const and non-zero pointer ranges as invariant. * gimple-range.cc (gimple_ranger::range_of_stmt): Remove pointer processing from here. gcc/testsuite/ PR tree-optimization/100512 * gcc.dg/pr100512.c: New.
[Bug tree-optimization/100512] [12 Regression] ICE during GIMPLE pass: cddce in mark_operand_necessary, at tree-ssa-dce.c:173 (under -O2 to -Os) since r12-623-g1416a1434c43de0b
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100512 --- Comment #7 from Andrew Macleod --- # e_25 = PHI _3 = e_25 + 1; if (_3 != 0) goto ; [INV] else goto ; [INV] <...> : # e_26 = PHI in order to take the edge 3->9, _3 must be [0,0]. _27 is used before defined, so we now use UNDEFINED for that. This allows the PHI to be folded to [0,0] This in turn feeds the PHI for e_25, and means e_25 must be [0,0] _3 is now confidently calculated as [0,0] + 1, making it [1,1] BUT. we just concluded that _3 must be [0,0] in order to feed the PHI, so ranger now decides that means _3 and e_26 are actually UNDEFINED.. which is true. This entire hunk of code is about to be removed, so we don't really need to do anything to it. However, the early VRP pass has concluded that since e_26 and _3 are constants, we can propagate the constant value. It does not consider UNDEFINED to be a constant value, so the propagation code was trapping because it had eliminated the definition of e_26, expecting it to be replaced with [0,0], not UNDEFINED. Probably the best way to fix this entire class of propagation errors is to do what we do with non-zero pointers. Once we get to a globally constant range where further refinements can only end up in an UNDEFINED state, stop further evaluating the range. This typically happens in places which are about to be removed by CFG cleanup anyway. Patch is in testing
[Bug tree-optimization/100512] [12 Regression] ICE during GIMPLE pass: cddce in mark_operand_necessary, at tree-ssa-dce.c:173 (under -O2 to -Os) since r12-623-g1416a1434c43de0b
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100512 Aldy Hernandez changed: What|Removed |Added CC||zhendong.su at inf dot ethz.ch --- Comment #6 from Aldy Hernandez --- *** Bug 100636 has been marked as a duplicate of this bug. ***
[Bug tree-optimization/100512] [12 Regression] ICE during GIMPLE pass: cddce in mark_operand_necessary, at tree-ssa-dce.c:173 (under -O2 to -Os) since r12-623-g1416a1434c43de0b
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100512 --- Comment #5 from Aldy Hernandez --- *** Bug 100578 has been marked as a duplicate of this bug. ***
[Bug tree-optimization/100512] [12 Regression] ICE during GIMPLE pass: cddce in mark_operand_necessary, at tree-ssa-dce.c:173 (under -O2 to -Os) since r12-623-g1416a1434c43de0b
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100512
--- Comment #4 from Aldy Hernandez ---
After the mentioned commit, e_27(D) is considered undefined, and since
_3 is [0,0], e_26 folds to [0,0] and the PHI is marked for removal:
# e_26 = PHI
However, when propagating to the uses of e_26 (replace_uses_in) here:
if (e_26 != 0)
...value_of_expr() returns NULL, because get_non_stale_global_range()
considers the value of e_26 stale:
if (m_globals.get_global_range (r, name))
{
if (m_temporal->current_p (name))
return true;
}
The dependencies for e_26 are e_27 and _3, per the PHI, but _3 has a
later time stamp.
The full IL follows. Notice the interdependence between e_26 and _3.
void b ()
{
int16_t i;
uint64_t * f;
uint64_t e;
uint16_t d;
int16_t * c;
long unsigned int _3;
long int d.3_5;
short int _7;
int a.5_8;
int iftmp.4_11;
:
d = 2;
// predicted unlikely by goto predictor.
goto ; [INV]
:
# e_25 = PHI
_3 = e_25 + 1;
if (_3 != 0)
goto ; [INV]
else
goto ; [INV]
:
goto ; [INV]
:
d.3_5 = (long int)
i_19 = (int16_t) d.3_5;
if (i_19 != 0)
goto ; [INV]
else
goto ; [INV]
:
if (e_26 != 0)
goto ; [INV]
else
goto ; [INV]
:
:
# iftmp.4_11 = PHI <1(6), 0(7)>
_7 = (short int) iftmp.4_11;
*c_22(D) = _7;
goto ; [INV]
:
# e_26 = PHI
g:
:
a.5_8 = a;
if (a.5_8 != 0)
goto ; [INV]
else
goto ; [INV]
}
[Bug tree-optimization/100512] [12 Regression] ICE during GIMPLE pass: cddce in mark_operand_necessary, at tree-ssa-dce.c:173 (under -O2 to -Os) since r12-623-g1416a1434c43de0b
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100512 Martin Liška changed: What|Removed |Added Summary|[12 Regression] ICE during |[12 Regression] ICE during |GIMPLE pass: cddce in |GIMPLE pass: cddce in |mark_operand_necessary, at |mark_operand_necessary, at |tree-ssa-dce.c:173 (under |tree-ssa-dce.c:173 (under |-O2 to -Os) |-O2 to -Os) since ||r12-623-g1416a1434c43de0b CC||marxin at gcc dot gnu.org --- Comment #3 from Martin Liška --- Started with r12-623-g1416a1434c43de0b.
[Bug tree-optimization/100512] [12 Regression] ICE during GIMPLE pass: cddce in mark_operand_necessary, at tree-ssa-dce.c:173 (under -O2 to -Os)
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100512 Richard Biener changed: What|Removed |Added Last reconfirmed||2021-05-11 CC||aldyh at gcc dot gnu.org, ||amacleod at redhat dot com Target Milestone|--- |12.0 Status|UNCONFIRMED |NEW Ever confirmed|0 |1 --- Comment #2 from Richard Biener --- checking reveals during GIMPLE pass: evrp t.c:21:1: internal compiler error: tree check: expected class 'type', have 'exceptional' (error_mark) in useless_type_conversion_p, at gimple-expr.c:88 21 | } | ^ 0x17569f1 tree_class_check_failed(tree_node const*, tree_code_class, char const*, int, char const*) /home/rguenther/src/gcc3/gcc/tree.c:8724 0xa2a9cb tree_class_check(tree_node*, tree_code_class, char const*, int, char const*) /home/rguenther/src/gcc3/gcc/tree.h:3479 0xec8f6c useless_type_conversion_p(tree_node*, tree_node*) /home/rguenther/src/gcc3/gcc/gimple-expr.c:88 0x138e103 verify_gimple_comparison /home/rguenther/src/gcc3/gcc/tree-cfg.c:3515 0x13946ef verify_gimple_cond /home/rguenther/src/gcc3/gcc/tree-cfg.c:4945 that's in if (_26 != 0) where we have a released SSA name.
[Bug tree-optimization/100512] [12 Regression] ICE during GIMPLE pass: cddce in mark_operand_necessary, at tree-ssa-dce.c:173 (under -O2 to -Os)
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100512 --- Comment #1 from Haoxin Tu --- (In reply to Haoxin Tu from comment #0) > $gcc -w -O2 Sorry, it's an incomplete command here. It should be "gcc -w -O2 small.c".
