https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126876
Manjunath S Matti <mmatti at linux dot vnet.ibm.com> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |mmatti at linux dot
vnet.ibm.com
--- Comment #11 from Manjunath S Matti <mmatti at linux dot vnet.ibm.com> ---
This also breaks bootstrap on both powerpc64le-unknown-linux-gnu and
powerpc64-unknown-linux-gnu. Trunk r17-3337-ge7b77e39552d, configured with
../gcc/configure --prefix=... --enable-languages=c,c++,fortran,objc,obj-c++ \
--with-cpu=power10 --enable-secureplt
Both endians die in stage 3 on the same translation unit:
during GIMPLE pass: thread
../../gcc/libcpp/lex.cc: In function 'void _cpp_clean_line(cpp_reader*)':
../../gcc/libcpp/lex.cc:970:1: internal compiler error: Segmentation fault
970 | _cpp_clean_line (cpp_reader *pfile)
| ^~~~~~~~~~~~~~~
0x12362e70 path_range_query::ssa_range_in_phi(vrange&, gphi*)
../../gcc/gcc/gimple-range-path.cc:262
0x1236323f path_range_query::range_defined_in_block(vrange&, tree_node*,
basic_block_def*)
../../gcc/gcc/gimple-range-path.cc:303
0x12362753 path_range_query::internal_range_of_expr(vrange&, tree_node*,
gimple*)
../../gcc/gcc/gimple-range-path.cc:160
[...]
make[3]: *** [Makefile:227: lex.o] Error 1
To unblock our ppc64 toolchain builds we are carrying the conservative guard
below. Posting it for information rather than as a proposed fix - if the
answer
is that these nested queries should go to the root ranger instead, that is
clearly the better fix.
--- a/gcc/gimple-range-path.cc
+++ b/gcc/gimple-range-path.cc
@@ -256,6 +256,14 @@ path_range_query::ssa_range_in_phi (vrange &r, gphi *phi)
basic_block bb = gimple_bb (phi);
basic_block prev = prev_bb ();
edge e_in = find_edge (prev, bb);
+ // The fold machinery can invoke this query (via get_range_query) for a
+ // PHI which is not at the current position in the path, in which case
+ // there is no path edge to select an argument from.
+ if (!e_in)
+ {
+ r.set_varying (TREE_TYPE (name));
+ return;
+ }
// The incoming edge the path supplies is never abnormal, so the
// argument on it is a valid value for the PHI result even when the
// result occurs in an abnormal PHI.
With it, the stage 3 libcpp/lex.cc that used to ICE compiles, and both reduced
testcases in comment #2 and comment #9 compile clean. gcc.dg/tree-ssa shows no
change (the only non-execution failure, update-threading.c "Invalid sum", is
already there without the patch). Full bootstraps on both endians are running
now; I will report back.
