https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68150
Bug ID: 68150
Summary: postreload-gcc ignores partially clobbered registers
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: rtl-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: segher at gcc dot gnu.org
Target Milestone: ---
postreload-gcse ("gcse2") does not take into account partially clobbered
registers, that is, HARD_REGNO_CALL_PART_CLOBBERED. This can be observed
e.g. with gcc.c-torture/execute/memcpy-bi.c when compiled for rs6000 with
options "-O3 -m32 -mpowerpc64 -mlra": it CSEs various DImode values over
calls although only the (low) SImode part of the integer registers is
preserved over calls, making the test fail.
