[llvm] [SDAG] Ensure load is included in output chain of sincos expansion (PR #140525)

[Matt Arsenault via llvm-commits]

================
@@ -0,0 +1,63 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --no_x86_scrub_sp --no_x86_scrub_mem_shuffle --version 5
+; RUN: llc < %s | FileCheck %s
+
+target triple = "x86_64-sie-ps5"
+
+declare hidden void @use_ptr(ptr readonly) local_unnamed_addr
+
+define hidden noundef i32 @sincos_stack_slot_with_lifetime(float %in) local_unnamed_addr {
----------------
arsenm wrote:

```suggestion
declare void @use_ptr(ptr readonly) 

define i32 @sincos_stack_slot_with_lifetime(float %in) {
```

https://github.com/llvm/llvm-project/pull/140525