[Bug tree-optimization/94784] ICE: in simplify_vector_constructor, at tree-ssa-forwprop.c:2482
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94784 rsandifo at gcc dot gnu.org changed: What|Removed |Added CC||rsandifo at gcc dot gnu.org Resolution|--- |FIXED Status|UNCONFIRMED |RESOLVED --- Comment #4 from rsandifo at gcc dot gnu.org --- Fixed on trunk.
[Bug tree-optimization/94784] ICE: in simplify_vector_constructor, at tree-ssa-forwprop.c:2482
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94784 --- Comment #3 from CVS Commits --- The master branch has been updated by Richard Sandiford : https://gcc.gnu.org/g:5328710be314dee43da8027dbff547d48b85e35e commit r10-7987-g5328710be314dee43da8027dbff547d48b85e35e Author: Fei Yang Date: Mon Apr 27 11:08:04 2020 +0100 forwprop: Fix ICE when building an identity constructor [PR94784] In the testcase for PR94784, we have two vectors with the same ABI identity but with different TYPE_MODEs. It would be better to flip the assert around so that it checks that the two vectors have equal TYPE_VECTOR_SUBPARTS and that converting the corresponding element types is a useless_type_conversion_p. 2020-04-27 Felix Yang gcc/ PR tree-optimization/94784 * tree-ssa-forwprop.c (simplify_vector_constructor): Flip the assert around so that it checks that the two vectors have equal TYPE_VECTOR_SUBPARTS and that converting the corresponding element types is a useless_type_conversion_p. gcc/testsuite/ PR tree-optimization/94784 * gcc.dg/pr94784.c: New test.
[Bug tree-optimization/94784] ICE: in simplify_vector_constructor, at tree-ssa-forwprop.c:2482
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94784 --- Comment #2 from Fei Yang --- Will propose a patch for review.
[Bug tree-optimization/94784] ICE: in simplify_vector_constructor, at tree-ssa-forwprop.c:2482
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94784 --- Comment #1 from Fei Yang --- I did some check and it looks like everything works fine before the ICE. The reason for the assert is that applying VIEW_CONVERT_EXPR to two general vectors is dangerous in this context. If through some bug we ended up with one vector being V4HI and the other being V2SI (say), the assert stops us from silently miscompiling the code. In the testcase we have two vectors with the same ABI identity but with different TYPE_MODEs. As suggested by Richard Sandiford, it would be better to flip the assert around so that it checks that the two vectors have equal TYPE_VECTOR_SUBPARTS and that converting the corresponding element types is a useless_type_conversion_p.
