x86: Check invalid third argument to __builtin_ia32_prefetch

Check invalid third argument to __builtin_ia32_prefetch when expaning
__builtin_ia32_prefetch to avoid ICE later.

gcc/

	PR target/108436
	* config/i386/i386-expand.cc (ix86_expand_builtin): Check
	invalid third argument to __builtin_ia32_prefetch.

gcc/testsuite/

	* gcc.target/i386/pr108436.c: New test.

Author: hjl-tools

gcc/config/i386/i386-expand.cc

@@ -13175,6 +13175,12 @@ ix86_expand_builtin (tree exp, rtx target, rtx subtarget,
 
 	if (INTVAL (op3) == 1)
 	  {
+	    if (INTVAL (op2) < 2 || INTVAL (op2) > 3)
+	      {
+		error ("invalid third argument");
+		return const0_rtx;
+	      }
+
 	    if (TARGET_64BIT && TARGET_PREFETCHI
 		&& local_func_symbolic_operand (op0, GET_MODE (op0)))
 	      emit_insn (gen_prefetchi (op0, op2));
@@ -13195,6 +13201,12 @@ ix86_expand_builtin (tree exp, rtx target, rtx subtarget,
 		op0 = copy_addr_to_reg (op0);
 	      }
 
+	    if (INTVAL (op2) < 0 || INTVAL (op2) > 3)
+	      {
+		warning (0, "invalid third argument to %<__builtin_ia32_prefetch%>; using zero");
+		op2 = const0_rtx;
+	      }
+
 	    if (TARGET_3DNOW || TARGET_PREFETCH_SSE
 		|| TARGET_PRFCHW || TARGET_PREFETCHWT1)
 	      emit_insn (gen_prefetch (op0, op1, op2));

gcc/testsuite/gcc.target/i386/pr108436.c

@@ -0,0 +1,15 @@
+/* { dg-do compile } */
+/* { dg-options "-mprefetchi" } */
+
+int
+foo (int a)
+{
+  return a + 1;
+}
+
+void
+bad (int *p)
+{
+  __builtin_ia32_prefetch (p, 0, 4, 0);   /* { dg-warning "invalid third argument to '__builtin_ia32_prefetch'; using zero" } */
+  __builtin_ia32_prefetch (foo, 0, 4, 1);   /* { dg-error "invalid third argument" } */
+}