function: Call do_pending_stack_adjust in assign_parms [PR117296]

Functions called by assign_parms call emit_block_move in two places,
so on some targets can be expanded as calls and can result in pending
stack adjustment.

Now, during expansion we normally call do_pending_stack_adjust at the end
of expansion of each basic block or before emitting code that will branch
and/or has labels, and when emitting labels we assert that there are no
pending stack adjustments.

assign_parms is expanded before the first basic block and if the first
basic block starts with a label and at least one of those emit_block_move
calls resulted in the need of pending stack adjustments, we ICE when
emitting that label.

The following patch fixes that by calling do_pending_stack_adjust after
after the assign_parms potential emit_block_move calls.

2024-10-30  Jakub Jelinek  <jakub@redhat.com>

	PR target/117296
	* function.cc (assign_parms): Call do_pending_stack_adjust.

	* gcc.target/i386/pr117296.c: New test.

gcc/function.cc

@@ -3747,6 +3747,8 @@ assign_parms (tree fndecl)
      now that all parameters have been copied out of hard registers.  */
   emit_insn (all.first_conversion_insn);
 
+  do_pending_stack_adjust ();
+
   /* Estimate reload stack alignment from scalar return mode.  */
   if (SUPPORTS_STACK_ALIGNMENT)
     {

gcc/testsuite/gcc.target/i386/pr117296.c

@@ -0,0 +1,12 @@
+/* PR target/117296 */
+/* { dg-do compile } */
+/* { dg-options "-O1" } */
+/* { dg-additional-options "-mtune=k6 -mstringop-strategy=libcall -ffloat-store" { target ia32 } } */
+
+int x;
+
+void
+foo (_Complex double c)
+{
+ lab:;
+}