Add a function for getting the ABI of a call insn target

This patch replaces get_call_reg_set_usage with insn_callee_abi,
which returns the ABI of the target of a call insn.  The ABI's
full_reg_clobbers corresponds to regs_invalidated_by_call,
whereas many callers instead passed call_used_or_fixed_regs, i.e.:

  (regs_invalidated_by_call | fixed_reg_set)

The patch slavishly preserves the "| fixed_reg_set" for these callers;
later patches will clean this up.

2019-09-30  Richard Sandiford  <richard.sandiford@arm.com>

gcc/
	* target.def (insn_callee_abi): New hook.
	(remove_extra_call_preserved_regs): Delete.
	* doc/tm.texi.in (TARGET_INSN_CALLEE_ABI): New macro.
	(TARGET_REMOVE_EXTRA_CALL_PRESERVED_REGS): Delete.
	* doc/tm.texi: Regenerate.
	* targhooks.h (default_remove_extra_call_preserved_regs): Delete.
	* targhooks.c (default_remove_extra_call_preserved_regs): Delete.
	* config/aarch64/aarch64.c (aarch64_simd_call_p): Constify the
	insn argument.
	(aarch64_remove_extra_call_preserved_regs): Delete.
	(aarch64_insn_callee_abi): New function.
	(TARGET_REMOVE_EXTRA_CALL_PRESERVED_REGS): Delete.
	(TARGET_INSN_CALLEE_ABI): New macro.
	* rtl.h (get_call_fndecl): Declare.
	(cgraph_rtl_info): Fix formatting.  Tweak comment for
	function_used_regs.  Remove function_used_regs_valid.
	* rtlanal.c (get_call_fndecl): Moved from final.c
	* function-abi.h (insn_callee_abi): Declare.
	(target_function_abi_info): Mention insn_callee_abi.
	* function-abi.cc (fndecl_abi): Handle flag_ipa_ra in a similar
	way to get_call_reg_set_usage did.
	(insn_callee_abi): New function.
	* regs.h (get_call_reg_set_usage): Delete.
	* final.c: Include function-abi.h.
	(collect_fn_hard_reg_usage): Add fixed and stack registers to
	function_used_regs before the main loop rather than afterwards.
	Use insn_callee_abi instead of get_call_reg_set_usage.  Exit early
	if function_used_regs ends up not being useful.
	(get_call_fndecl): Move to rtlanal.c
	(get_call_cgraph_rtl_info, get_call_reg_set_usage): Delete.
	* caller-save.c: Include function-abi.h.
	(setup_save_areas, save_call_clobbered_regs): Use insn_callee_abi
	instead of get_call_reg_set_usage.
	* cfgcleanup.c: Include function-abi.h.
	(old_insns_match_p): Use insn_callee_abi instead of
	get_call_reg_set_usage.
	* cgraph.h (cgraph_node::rtl_info): Take a const_tree instead of
	a tree.
	* cgraph.c (cgraph_node::rtl_info): Likewise.  Initialize
	function_used_regs.
	* df-scan.c: Include function-abi.h.
	(df_get_call_refs): Use insn_callee_abi instead of
	get_call_reg_set_usage.
	* ira-lives.c: Include function-abi.h.
	(process_bb_node_lives): Use insn_callee_abi instead of
	get_call_reg_set_usage.
	* lra-lives.c: Include function-abi.h.
	(process_bb_lives): Use insn_callee_abi instead of
	get_call_reg_set_usage.
	* postreload.c: Include function-abi.h.
	(reload_combine): Use insn_callee_abi instead of
	get_call_reg_set_usage.
	* regcprop.c: Include function-abi.h.
	(copyprop_hardreg_forward_1): Use insn_callee_abi instead of
	get_call_reg_set_usage.
	* resource.c: Include function-abi.h.
	(mark_set_resources, mark_target_live_regs): Use insn_callee_abi
	instead of get_call_reg_set_usage.
	* var-tracking.c: Include function-abi.h.
	(dataflow_set_clear_at_call): Use insn_callee_abi instead of
	get_call_reg_set_usage.

From-SVN: r276309

1 files changed, 18 insertions, 0 deletions

diff --git a/gcc/rtlanal.c b/gcc/rtlanal.c
index 28b399c..9c70eee 100644
--- a/gcc/rtlanal.c
+++ b/gcc/rtlanal.c
@@ -822,6 +822,24 @@ get_call_rtx_from (const rtx_insn *insn)
     return x;
   return NULL_RTX;
 }
+
+/* Get the declaration of the function called by INSN.  */
+
+tree
+get_call_fndecl (const rtx_insn *insn)
+{
+  rtx note, datum;
+
+  note = find_reg_note (insn, REG_CALL_DECL, NULL_RTX);
+  if (note == NULL_RTX)
+    return NULL_TREE;
+
+  datum = XEXP (note, 0);
+  if (datum != NULL_RTX)
+    return SYMBOL_REF_DECL (datum);
+
+  return NULL_TREE;
+}
 
 /* Return the value of the integer term in X, if one is apparent;
    otherwise return 0.