https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77308
Bug ID: 77308 Summary: surprisingly large stack usage for sha512 on arm Product: gcc Version: 7.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: target Assignee: unassigned at gcc dot gnu.org Reporter: edlinger at gcc dot gnu.org Target Milestone: --- Created attachment 39479 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=39479&action=edit test case I've noticed that openssl with no-asm but without -DOPENSSL_SMALL_FOOTPRINT uses > 3600 byte of stack for a simple sha512 computation with -O3 on ARM. Which is surprising, because on i386 the same function uses only 1016 byte, and x86_64 uses only 256 bytes stack. See the attached source code witch is stripped down from sha512.c