https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104198
--- Comment #16 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Robin Dapp <rd...@gcc.gnu.org>: https://gcc.gnu.org/g:d0d4601ccde3c4849f6e7244035f1a899d608cb7 commit r12-7114-gd0d4601ccde3c4849f6e7244035f1a899d608cb7 Author: Robin Dapp <rd...@linux.ibm.com> Date: Tue Feb 8 16:11:20 2022 +0100 ifcvt: Fix PR104153 and PR104198. This is a bugfix for r12-6747-gaa8cfe785953a0 which caused an ICE on or1k (PR104153) and broke SPARC bootstrap (PR104198). cond_exec_get_condition () returns the jump condition directly and we now pass it to the backend. The or1k backend modified the condition in-place (other backends do that as well) but this modification is not reverted when the sequence in question is discarded. Therefore we copy the RTX instead of using it directly. The SPARC problem is due to the SPARC backend recreating the initial condition when being passed a CC comparison. This causes the sequence to read from an already overwritten condition operand. Generally, this could also happen on other targets. The workaround is to always first emit to a temporary. In a second run of noce_convert_multiple_sets_1 we know which sequences actually require the comparison and will use no temporaries if all sequences after the current one do not require it. PR rtl-optimization/104198 PR rtl-optimization/104153 gcc/ChangeLog: * ifcvt.cc (noce_convert_multiple_sets_1): Copy rtx instead of using it directly. Rework comparison handling and always perform a second pass. gcc/testsuite/ChangeLog: * gcc.dg/pr104198.c: New test.
