https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85399
Bug ID: 85399
Summary: Redundant SSP clearing before rdssp
Product: gcc
Version: 8.0.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: hjl.tools at gmail dot com
CC: igor.v.tsimbalist at intel dot com
Blocks: 81652
Target Milestone: ---
Since rdssp has been changed to
;; CET instructions
(define_insn "rdssp<mode>"
[(set (match_operand:SWI48x 0 "register_operand" "=r")
(unspec_volatile:SWI48x [(const_int 0)] UNSPECV_NOP_RDSSP))]
"TARGET_SHSTK"
"xor{l}\t%k0, %k0\n\trdssp<mskmodesuffix>\t%0"
[(set_attr "length" "6")
(set_attr "type" "other")])
emit_insn (gen_rtx_SET (reg_ssp, const0_rtx));
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ This is redundant now.
emit_insn ((word_mode == SImode)
? gen_rdsspsi (reg_ssp)
: gen_rdsspdi (reg_ssp));
Referenced Bugs:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81652
[Bug 81652] [meta-bug] -fcf-protection=full -mcet bugs
