cfg-flags.def reads:
/* Edge out of a basic block that ends with a CALL_INSN with abnormal
exit, like an exception, or a sibcall.
This flag is only used for the RTL CFG. */
DEF_EDGE_FLAG(ABNORMAL_CALL, 2)
That's wrong, ABNORMAL_CALL isn't set for a sibcall, only ABNORMAL is.
That's even asserted in purge_dead_edges:
else if (CALL_P (insn) && SIBLING_CALL_P (insn))
{
/* First, there should not be any EH or ABCALL edges resulting
from non-local gotos and the like. If there were, we shouldn't
have created the sibcall in the first place. Second, there
should of course never have been a fallthru edge. */
gcc_assert (single_succ_p (bb));
gcc_assert (single_succ_edge (bb)->flags
== (EDGE_SIBCALL | EDGE_ABNORMAL));
return 0;
}
This means that the EDGE_ABNORMAL check in rtl_verify_flow_info_1 is wrong as
well. But it contains a thinko that masks the bug. :-)
Tested on x86_64-suse-linux, applied on the mainline.
2012-11-02 Eric Botcazou <ebotca...@adacore.com>
* cfg-flags.def (ABNORMAL_CALL): Fix comment.
(EH): Likewise.
(SIBCALL): Likewise.
* cfgrtl.c (rtl_verify_flow_info_1): Adjust error messages.
Deal with EDGE_SIBCALL and fix the EDGE_ABNORMAL check.
--
Eric BotcazouIndex: cfg-flags.def
===================================================================
--- cfg-flags.def (revision 193090)
+++ cfg-flags.def (working copy)
@@ -115,13 +115,14 @@ DEF_EDGE_FLAG(FALLTHRU, 0)
DEF_EDGE_FLAG(ABNORMAL, 1)
/* Edge out of a basic block that ends with a CALL_INSN with abnormal
- exit, like an exception, or a sibcall.
+ exit, like an exception or a non-local goto.
+ ABNORMAL_CALL edges also have ABNORMAL set.
This flag is only used for the RTL CFG. */
DEF_EDGE_FLAG(ABNORMAL_CALL, 2)
/* Exception edge. Exception handling edges represent possible control
- transfers from a trapping instruction to an exception handler. EH
- edges also have EDGE_ABNORMAL set. */
+ transfers from a trapping instruction to an exception handler.
+ EH edges also have ABNORMAL set for the RTL CFG. */
DEF_EDGE_FLAG(EH, 3)
/* Never merge blocks via this edge. This is used for exception handling,
@@ -158,6 +159,7 @@ DEF_EDGE_FLAG(EXECUTABLE, 10)
DEF_EDGE_FLAG(CROSSING, 11)
/* Edge from a sibcall CALL_INSN to exit.
+ SIBCALL edges also have ABNORMAL set.
This flag is only used for the RTL CFG. */
DEF_EDGE_FLAG(SIBCALL, 12)
Index: cfgrtl.c
===================================================================
--- cfgrtl.c (revision 193090)
+++ cfgrtl.c (working copy)
@@ -2095,7 +2095,8 @@ rtl_verify_flow_info_1 (void)
/* Now check the basic blocks (boundaries etc.) */
FOR_EACH_BB_REVERSE (bb)
{
- int n_fallthru = 0, n_eh = 0, n_call = 0, n_abnormal = 0, n_branch = 0;
+ int n_fallthru = 0, n_branch = 0, n_abnormal_call = 0, n_sibcall = 0;
+ int n_eh = 0, n_abnormal = 0;
edge e, fallthru = NULL;
rtx note;
edge_iterator ei;
@@ -2132,13 +2133,13 @@ rtl_verify_flow_info_1 (void)
}
if (e->flags & EDGE_FALLTHRU)
{
- error ("fallthru edge crosses section boundary (bb %i)",
+ error ("fallthru edge crosses section boundary in bb %i",
e->src->index);
err = 1;
}
if (e->flags & EDGE_EH)
{
- error ("EH edge crosses section boundary (bb %i)",
+ error ("EH edge crosses section boundary in bb %i",
e->src->index);
err = 1;
}
@@ -2158,22 +2159,26 @@ rtl_verify_flow_info_1 (void)
n_branch++;
if (e->flags & EDGE_ABNORMAL_CALL)
- n_call++;
+ n_abnormal_call++;
+
+ if (e->flags & EDGE_SIBCALL)
+ n_sibcall++;
if (e->flags & EDGE_EH)
n_eh++;
- else if (e->flags & EDGE_ABNORMAL)
+
+ if (e->flags & EDGE_ABNORMAL)
n_abnormal++;
}
if (n_eh && !find_reg_note (BB_END (bb), REG_EH_REGION, NULL_RTX))
{
- error ("missing REG_EH_REGION note in the end of bb %i", bb->index);
+ error ("missing REG_EH_REGION note at the end of bb %i", bb->index);
err = 1;
}
if (n_eh > 1)
{
- error ("too many eh edges %i", bb->index);
+ error ("too many exception handling edges in bb %i", bb->index);
err = 1;
}
if (n_branch
@@ -2186,29 +2191,35 @@ rtl_verify_flow_info_1 (void)
}
if (n_fallthru && any_uncondjump_p (BB_END (bb)))
{
- error ("fallthru edge after unconditional jump %i", bb->index);
+ error ("fallthru edge after unconditional jump in bb %i", bb->index);
err = 1;
}
if (n_branch != 1 && any_uncondjump_p (BB_END (bb)))
{
- error ("wrong number of branch edges after unconditional jump %i",
- bb->index);
+ error ("wrong number of branch edges after unconditional jump"
+ " in bb %i", bb->index);
err = 1;
}
if (n_branch != 1 && any_condjump_p (BB_END (bb))
&& JUMP_LABEL (BB_END (bb)) != BB_HEAD (fallthru->dest))
{
- error ("wrong amount of branch edges after conditional jump %i",
- bb->index);
+ error ("wrong amount of branch edges after conditional jump"
+ " in bb %i", bb->index);
+ err = 1;
+ }
+ if (n_abnormal_call && !CALL_P (BB_END (bb)))
+ {
+ error ("abnormal call edges for non-call insn in bb %i", bb->index);
err = 1;
}
- if (n_call && !CALL_P (BB_END (bb)))
+ if (n_sibcall && !CALL_P (BB_END (bb)))
{
- error ("call edges for non-call insn in bb %i", bb->index);
+ error ("sibcall edges for non-call insn in bb %i", bb->index);
err = 1;
}
- if (n_abnormal
- && (!CALL_P (BB_END (bb)) && n_call != n_abnormal)
+ if (n_abnormal > n_eh
+ && !(CALL_P (BB_END (bb))
+ && n_abnormal == n_abnormal_call + n_sibcall)
&& (!JUMP_P (BB_END (bb))
|| any_condjump_p (BB_END (bb))
|| any_uncondjump_p (BB_END (bb))))
