From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2153) id B55E4384BC11; Mon, 31 May 2021 14:08:33 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org B55E4384BC11 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Jakub Jelinek To: gcc-cvs@gcc.gnu.org Subject: [gcc r11-8488] regcprop: Avoid DCE of asm goto [PR100590] X-Act-Checkin: gcc X-Git-Author: Jakub Jelinek X-Git-Refname: refs/heads/releases/gcc-11 X-Git-Oldrev: c4d64d136e4e35fb2ee90771848944bb2ffeaf85 X-Git-Newrev: 490ffb47ad10df1793c4894c7c888d7a10576f1a Message-Id: <20210531140833.B55E4384BC11@sourceware.org> Date: Mon, 31 May 2021 14:08:33 +0000 (GMT) X-BeenThere: gcc-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 31 May 2021 14:08:33 -0000 https://gcc.gnu.org/g:490ffb47ad10df1793c4894c7c888d7a10576f1a commit r11-8488-g490ffb47ad10df1793c4894c7c888d7a10576f1a Author: Jakub Jelinek Date: Tue May 18 10:26:45 2021 +0200 regcprop: Avoid DCE of asm goto [PR100590] The following testcase ICEs, because copyprop_hardreg_forward_1 decides to DCE asm goto with REG_UNUSED notes (because the output is unused and asm isn't volatile). But that DCE just removes the asm goto, leaving a bb with two successors and no insn at the end that would allow that. The following patch makes sure we drop that way only INSNs and not JUMP_INSNs or CALL_INSNs. 2021-05-18 Jakub Jelinek PR rtl-optimization/100590 * regcprop.c (copyprop_hardreg_forward_1): Only DCE dead sets if they are NONJUMP_INSN_P. * gcc.dg/pr100590.c: New test. (cherry picked from commit c81704b359283bb54696755ead881ab04136da94) Diff: --- gcc/regcprop.c | 1 + gcc/testsuite/gcc.dg/pr100590.c | 13 +++++++++++++ 2 files changed, 14 insertions(+) diff --git a/gcc/regcprop.c b/gcc/regcprop.c index 7c271e22f47..44f6295b516 100644 --- a/gcc/regcprop.c +++ b/gcc/regcprop.c @@ -808,6 +808,7 @@ copyprop_hardreg_forward_1 (basic_block bb, struct value_data *vd) /* Detect obviously dead sets (via REG_UNUSED notes) and remove them. */ if (set && !RTX_FRAME_RELATED_P (insn) + && NONJUMP_INSN_P (insn) && !may_trap_p (set) && find_reg_note (insn, REG_UNUSED, SET_DEST (set)) && !side_effects_p (SET_SRC (set)) diff --git a/gcc/testsuite/gcc.dg/pr100590.c b/gcc/testsuite/gcc.dg/pr100590.c new file mode 100644 index 00000000000..5cd36877fa1 --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr100590.c @@ -0,0 +1,13 @@ +/* PR rtl-optimization/100590 */ +/* { dg-do compile } */ +/* { dg-options "-O1 -fno-dce -w" } */ + +int +foo (void) +{ + int x; + asm goto ("" : "+r" (x) : : : lab); + return 0; + lab: + return 1; +}