[Bug tree-optimization/115426] ICE: in execute_todo, at passes.cc:2138
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115426 Richard Biener changed: What|Removed |Added Target Milestone|--- |14.3 Status|ASSIGNED|RESOLVED Resolution|--- |FIXED Known to fail||14.2.0 Known to work||14.2.1 --- Comment #7 from Richard Biener --- Fixed for GCC 14, not backporting further (the testcase looks artificially generated, not from real-world code).
[Bug tree-optimization/115426] ICE: in execute_todo, at passes.cc:2138
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115426
--- Comment #6 from GCC Commits ---
The releases/gcc-14 branch has been updated by Richard Biener
:
https://gcc.gnu.org/g:5b264a4b95b8f27c3c73892892d5c2030d3c8ea7
commit r14-10685-g5b264a4b95b8f27c3c73892892d5c2030d3c8ea7
Author: Richard Biener
Date: Tue Jun 11 13:11:08 2024 +0200
middle-end/115426 - wrong gimplification of "rm" asm output operand
When the operand is gimplified to an extract of a register or a
register we have to disallow memory as we otherwise fail to
gimplify it properly. Instead of
__asm__("" : "=rm" __imag );
we want
__asm__("" : "=rm" D.2772);
_1 = REALPART_EXPR ;
r = COMPLEX_EXPR <_1, D.2772>;
otherwise SSA rewrite will fail and generate wrong code with 'r'
left bare in the asm output.
PR middle-end/115426
* gimplify.cc (gimplify_asm_expr): Handle "rm" output
constraint gimplified to a register (operation).
* gcc.dg/pr115426.c: New testcase.
(cherry picked from commit a4bbdec2be1c9f8fb49276b8a54ee86024ceac17)
[Bug tree-optimization/115426] ICE: in execute_todo, at passes.cc:2138
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115426 Richard Biener changed: What|Removed |Added Known to work||15.0 Keywords|ice-on-invalid-code |ice-on-valid-code --- Comment #5 from Richard Biener --- Fixed on trunk sofar (I think the final testcases are valid).
[Bug tree-optimization/115426] ICE: in execute_todo, at passes.cc:2138
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115426
--- Comment #4 from GCC Commits ---
The master branch has been updated by Richard Biener :
https://gcc.gnu.org/g:a4bbdec2be1c9f8fb49276b8a54ee86024ceac17
commit r15-1837-ga4bbdec2be1c9f8fb49276b8a54ee86024ceac17
Author: Richard Biener
Date: Tue Jun 11 13:11:08 2024 +0200
middle-end/115426 - wrong gimplification of "rm" asm output operand
When the operand is gimplified to an extract of a register or a
register we have to disallow memory as we otherwise fail to
gimplify it properly. Instead of
__asm__("" : "=rm" __imag );
we want
__asm__("" : "=rm" D.2772);
_1 = REALPART_EXPR ;
r = COMPLEX_EXPR <_1, D.2772>;
otherwise SSA rewrite will fail and generate wrong code with 'r'
left bare in the asm output.
PR middle-end/115426
* gimplify.cc (gimplify_asm_expr): Handle "rm" output
constraint gimplified to a register (operation).
* gcc.dg/pr115426.c: New testcase.
[Bug tree-optimization/115426] ICE: in execute_todo, at passes.cc:2138
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115426
--- Comment #3 from Richard Biener ---
I think this is a gimplification failure. 'r' is neither TREE_ADDRESSABLE
nor DECL_NOT_GIMPLE_REG and the =X constraint results in both allow_reg
and allow_mem but we gimplify it as is_gimple_lvalue which should,
as the base is a gimple register, emit a component extract to pre_p and
a complex build to post_p.
gimplify_compound_lval correctly sees this and forces a register argument
to the __imag operation but I'm not sure that's enough for lvalues.
IIRC a simple
__imag x = 1;
also doesn't have DECL_NOT_GIMPLE_REG on 'x', and gimplify_compound_lval
behaves the same. Still we eventually gimplify to
_1 = REALPART_EXPR ;
x = COMPLEX_EXPR <_1, 1.0e+0>;
D.2772 = x;
which is done via gimplify_modify_expr_complex_part. That suggests
it's gimplify_asm_expr that would need to do this very same thing as we
seem to rely on this for correctness.
With "=r" we correctly gimplify to
__asm__("" : "=r" D.2772);
_1 = REALPART_EXPR ;
r = COMPLEX_EXPR <_1, D.2772>;
D.2773 = r;
[Bug tree-optimization/115426] ICE: in execute_todo, at passes.cc:2138
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115426 Richard Biener changed: What|Removed |Added Assignee|unassigned at gcc dot gnu.org |rguenth at gcc dot gnu.org Status|NEW |ASSIGNED --- Comment #2 from Richard Biener --- Mine (into-SSA is broken it seems)
[Bug tree-optimization/115426] ICE: in execute_todo, at passes.cc:2138
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115426
Andrew Pinski changed:
What|Removed |Added
Last reconfirmed||2024-06-11
Ever confirmed|0 |1
Status|UNCONFIRMED |NEW
--- Comment #1 from Andrew Pinski ---
Reduced testcase that ICEs on all targets:
```
_Complex float fcs() {
_Complex float r;
__asm__("" : "=X" (__imag__ r) );
return r;
}
```
Looks like this has been ICEing for a while with checking enabled.
