From fca790eb60478652025f6604d5b57152cb5160c9 Mon Sep 17 00:00:00 2001 From: Jeffrey A Law Date: Wed, 16 May 2001 04:12:33 +0000 Subject: [PATCH] flow.c (life_analysis): After life analysis is complete... * flow.c (life_analysis): After life analysis is complete, do an optional scan over insns looking for REG_LABEL notes that reference a deleted label. (propagate_block_delete_insn): Verify INOTE is a CODE_LABEL before peeking at LABEL_NUSES. From-SVN: r42131 --- gcc/ChangeLog | 8 ++++++++ gcc/flow.c | 28 ++++++++++++++++++++++++++-- 2 files changed, 34 insertions(+), 2 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index b624dbfcb2b..d0f8dfe744e 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,11 @@ +Tue May 15 22:14:09 2001 Jeffrey A Law (law@cygnus.com) + + * flow.c (life_analysis): After life analysis is complete, do + an optional scan over insns looking for REG_LABEL notes that + reference a deleted label. + (propagate_block_delete_insn): Verify INOTE is a CODE_LABEL + before peeking at LABEL_NUSES. + 2001-05-15 Richard Henderson * unwind-sjlj.c (_Unwind_GetDataRelBase): New. diff --git a/gcc/flow.c b/gcc/flow.c index 96d2ad040a4..d983ab5d24d 100644 --- a/gcc/flow.c +++ b/gcc/flow.c @@ -2854,6 +2854,21 @@ life_analysis (f, file, flags) dump_flow_info (file); free_basic_block_vars (1); + +#ifdef ENABLE_CHECKING + { + rtx insn; + + /* Search for any REG_LABEL notes whih reference deleted labels. */ + for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) + { + rtx inote = find_reg_note (insn, REG_LABEL, NULL_RTX); + + if (inote && GET_CODE (inote) == NOTE_INSN_DELETED_LABEL) + abort (); + } + } +#endif } /* A subroutine of verify_wide_reg, called through for_each_rtx. @@ -3631,9 +3646,18 @@ propagate_block_delete_insn (bb, insn) /* If the insn referred to a label, and that label was attached to an ADDR_VEC, it's safe to delete the ADDR_VEC. In fact, it's pretty much mandatory to delete it, because the ADDR_VEC may be - referencing labels that no longer exist. */ + referencing labels that no longer exist. + + INSN may reference a deleted label, particularly when a jump + table has been optimized into a direct jump. There's no + real good way to fix up the reference to the deleted label + when the label is deleted, so we just allow it here. + + After dead code elimination is complete, we do search for + any REG_LABEL notes which reference deleted labels as a + sanity check. */ - if (inote) + if (inote && GET_CODE (inote) == CODE_LABEL) { rtx label = XEXP (inote, 0); rtx next; -- 2.11.4.GIT