+2002-03-19 Richard Henderson <rth@redhat.com>
+
+ * flow.c (EH_USES): Provide default.
+ (calculate_global_regs_live): Use it for EH edges and noreturn calls.
+ * doc/tm.texi (EH_USES): New.
+
+ * config/ia64/ia64.c (ia64_eh_uses): New.
+ * config/ia64/ia64-protos.h: Update.
+ * config/ia64/ia64.h (EH_USES): New.
+
2002-03-19 Richard Henderson <rth@redhat.com>
* varasm.c (output_constant_def): Fix stupid typo.
return 0;
}
}
+
+/* Return true if REGNO is used by the frame unwinder. */
+
+int
+ia64_eh_uses (regno)
+ int regno;
+{
+ if (! reload_completed)
+ return 0;
+
+ if (current_frame_info.reg_save_b0
+ && regno == current_frame_info.reg_save_b0)
+ return 1;
+ if (current_frame_info.reg_save_pr
+ && regno == current_frame_info.reg_save_pr)
+ return 1;
+ if (current_frame_info.reg_save_ar_pfs
+ && regno == current_frame_info.reg_save_ar_pfs)
+ return 1;
+ if (current_frame_info.reg_save_ar_unat
+ && regno == current_frame_info.reg_save_ar_unat)
+ return 1;
+ if (current_frame_info.reg_save_ar_lc
+ && regno == current_frame_info.reg_save_ar_lc)
+ return 1;
+
+ return 0;
+}
\f
/* For ia64, SYMBOL_REF_FLAG set means that it is a function.
used by the epilogue or the @samp{return} pattern. The stack and frame
pointer registers are already be assumed to be used as needed.
+@findex EH_USES
+@item EH_USES (@var{regno})
+Define this macro as a C expression that is nonzero for registers that are
+used by the exception handling mechanism, and so should be considered live
+on entry to an exception edge.
+
@findex DELAY_SLOTS_FOR_EPILOGUE
@item DELAY_SLOTS_FOR_EPILOGUE
Define this macro if the function epilogue contains delay slots to which
#ifndef EPILOGUE_USES
#define EPILOGUE_USES(REGNO) 0
#endif
+#ifndef EH_USES
+#define EH_USES(REGNO) 0
+#endif
#ifdef HAVE_conditional_execution
#ifndef REVERSE_CONDEXEC_PREDICATES_P
/* Begin by propagating live_at_start from the successor blocks. */
CLEAR_REG_SET (new_live_at_end);
- for (e = bb->succ; e; e = e->succ_next)
- {
- basic_block sb = e->dest;
- /* Call-clobbered registers die across exception and call edges. */
- /* ??? Abnormal call edges ignored for the moment, as this gets
- confused by sibling call edges, which crashes reg-stack. */
- if (e->flags & EDGE_EH)
- {
- bitmap_operation (tmp, sb->global_live_at_start,
- call_used, BITMAP_AND_COMPL);
- IOR_REG_SET (new_live_at_end, tmp);
- }
- else
- IOR_REG_SET (new_live_at_end, sb->global_live_at_start);
+ if (bb->succ)
+ for (e = bb->succ; e; e = e->succ_next)
+ {
+ basic_block sb = e->dest;
+
+ /* Call-clobbered registers die across exception and
+ call edges. */
+ /* ??? Abnormal call edges ignored for the moment, as this gets
+ confused by sibling call edges, which crashes reg-stack. */
+ if (e->flags & EDGE_EH)
+ {
+ bitmap_operation (tmp, sb->global_live_at_start,
+ call_used, BITMAP_AND_COMPL);
+ IOR_REG_SET (new_live_at_end, tmp);
+ }
+ else
+ IOR_REG_SET (new_live_at_end, sb->global_live_at_start);
+
+ /* If a target saves one register in another (instead of on
+ the stack) the save register will need to be live for EH. */
+ if (e->flags & EDGE_EH)
+ for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
+ if (EH_USES (i))
+ SET_REGNO_REG_SET (new_live_at_end, i);
+ }
+ else
+ {
+ /* This might be a noreturn function that throws. And
+ even if it isn't, getting the unwind info right helps
+ debugging. */
+ for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
+ if (EH_USES (i))
+ SET_REGNO_REG_SET (new_live_at_end, i);
}
/* The all-important stack pointer must always be live. */