| Message ID | 20191123011536.GI2466@tucnak |
|---|---|
| State | New |
| Headers | show |
| Series | Perform cfg cleanup in cse if needed (PR rtl-optimization/92610) | expand |
On November 23, 2019 2:15:36 AM GMT+01:00, Jakub Jelinek <jakub@redhat.com> wrote: >Hi! > >cse_main which sets tem has: > if (cse_jumps_altered || recorded_label_ref) > return 2; > else if (cse_cfg_altered) > return 1; > else > return 0; >at the end, but after these two functions call it, they call also >delete_trivially_dead_insns. Even when cse_main didn't need cfg >changes, >delete_trivially_dead_insns could remove a trivially dead insn that had >EH edges and so we might still need to remove unreachable blocks. > >The following patch implements it. Bootstrapped/regtested on >x86_64-linux >and i686-linux, ok for trunk? Ok. Richard. >2019-11-23 Jakub Jelinek <jakub@redhat.com> > > PR rtl-optimization/92610 > * cse.c (rest_of_handle_cse2): Call cleanup_cfg (0) also if > cse_cfg_altered is set, even when tem is 0. > (rest_of_handle_cse_after_global_opts): Likewise. > > * g++.dg/opt/pr92610.C: New test. > >--- gcc/cse.c.jj 2019-11-19 22:27:01.960059340 +0100 >+++ gcc/cse.c 2019-11-22 15:51:34.639806155 +0100 >@@ -7701,7 +7701,7 @@ rest_of_handle_cse2 (void) > cse_cfg_altered |= cleanup_cfg (CLEANUP_CFG_CHANGED); > timevar_pop (TV_JUMP); > } >- else if (tem == 1) >+ else if (tem == 1 || cse_cfg_altered) > cse_cfg_altered |= cleanup_cfg (0); > > cse_not_expected = 1; >@@ -7775,7 +7775,7 @@ rest_of_handle_cse_after_global_opts (vo > cse_cfg_altered |= cleanup_cfg (CLEANUP_CFG_CHANGED); > timevar_pop (TV_JUMP); > } >- else if (tem == 1) >+ else if (tem == 1 || cse_cfg_altered) > cse_cfg_altered |= cleanup_cfg (0); > > flag_cse_follow_jumps = save_cfj; >--- gcc/testsuite/g++.dg/opt/pr92610.C.jj 2019-11-22 15:52:46.254734331 >+0100 >+++ gcc/testsuite/g++.dg/opt/pr92610.C 2019-11-22 15:53:14.991303498 >+0100 >@@ -0,0 +1,13 @@ >+// PR rtl-optimization/92610 >+// { dg-do compile } >+// { dg-options "-w -fdelete-dead-exceptions >--param=sccvn-max-alias-queries-per-access=0 -fno-dse >-fnon-call-exceptions -Os -funroll-loops -ftrapv" } >+ >+struct C { int x; ~C () {} }; >+ >+int >+main () >+{ >+ C *buffer = new C[42]; >+ buffer[-3].x = 42; >+ delete [] buffer; >+} > > Jakub
--- gcc/cse.c.jj 2019-11-19 22:27:01.960059340 +0100 +++ gcc/cse.c 2019-11-22 15:51:34.639806155 +0100 @@ -7701,7 +7701,7 @@ rest_of_handle_cse2 (void) cse_cfg_altered |= cleanup_cfg (CLEANUP_CFG_CHANGED); timevar_pop (TV_JUMP); } - else if (tem == 1) + else if (tem == 1 || cse_cfg_altered) cse_cfg_altered |= cleanup_cfg (0); cse_not_expected = 1; @@ -7775,7 +7775,7 @@ rest_of_handle_cse_after_global_opts (vo cse_cfg_altered |= cleanup_cfg (CLEANUP_CFG_CHANGED); timevar_pop (TV_JUMP); } - else if (tem == 1) + else if (tem == 1 || cse_cfg_altered) cse_cfg_altered |= cleanup_cfg (0); flag_cse_follow_jumps = save_cfj; --- gcc/testsuite/g++.dg/opt/pr92610.C.jj 2019-11-22 15:52:46.254734331 +0100 +++ gcc/testsuite/g++.dg/opt/pr92610.C 2019-11-22 15:53:14.991303498 +0100 @@ -0,0 +1,13 @@ +// PR rtl-optimization/92610 +// { dg-do compile } +// { dg-options "-w -fdelete-dead-exceptions --param=sccvn-max-alias-queries-per-access=0 -fno-dse -fnon-call-exceptions -Os -funroll-loops -ftrapv" } + +struct C { int x; ~C () {} }; + +int +main () +{ + C *buffer = new C[42]; + buffer[-3].x = 42; + delete [] buffer; +}
Hi! cse_main which sets tem has: if (cse_jumps_altered || recorded_label_ref) return 2; else if (cse_cfg_altered) return 1; else return 0; at the end, but after these two functions call it, they call also delete_trivially_dead_insns. Even when cse_main didn't need cfg changes, delete_trivially_dead_insns could remove a trivially dead insn that had EH edges and so we might still need to remove unreachable blocks. The following patch implements it. Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? 2019-11-23 Jakub Jelinek <jakub@redhat.com> PR rtl-optimization/92610 * cse.c (rest_of_handle_cse2): Call cleanup_cfg (0) also if cse_cfg_altered is set, even when tem is 0. (rest_of_handle_cse_after_global_opts): Likewise. * g++.dg/opt/pr92610.C: New test. Jakub