Struct & SIMD improvements (#22255)

* [WIP] Struct & SIMD improvements

- Enable CSE of struct values when handle is available (and add code to get the handle of HW SIMD types)
- Don't require block nodes for SIMD assignments
- Don't set `GTF_GLOB_REF` on `GT_OBJ` if it is local
- Set `lvRegStruct` on promoted SIMD fields
- Add tests for #19910 (fixed with this PR) and #3539 & #19438 (fixed with #21314)
- Additional cleanup

Fix #19910

1 files changed, 14 insertions, 8 deletions

diff --git a/src/jit/gentree.h b/src/jit/gentree.h
index ef3bca2667..6893c35ce4 100644
--- a/src/jit/gentree.h
+++ b/src/jit/gentree.h
@@ -4712,22 +4712,28 @@ struct GenTreeObj : public GenTreeBlk
         }
     }
 
+    void Init()
+    {
+        // By default, an OBJ is assumed to be a global reference, unless it is local.
+        GenTreeLclVarCommon* lcl = Addr()->IsLocalAddrExpr();
+        if ((lcl == nullptr) || ((lcl->gtFlags & GTF_GLOB_EFFECT) != 0))
+        {
+            gtFlags |= GTF_GLOB_REF;
+        }
+        noway_assert(gtClass != NO_CLASS_HANDLE);
+        _gtGcPtrCount = UINT32_MAX;
+    }
+
     GenTreeObj(var_types type, GenTree* addr, CORINFO_CLASS_HANDLE cls, unsigned size)
         : GenTreeBlk(GT_OBJ, type, addr, size), gtClass(cls)
     {
-        // By default, an OBJ is assumed to be a global reference.
-        gtFlags |= GTF_GLOB_REF;
-        noway_assert(cls != NO_CLASS_HANDLE);
-        _gtGcPtrCount = UINT32_MAX;
+        Init();
     }
 
     GenTreeObj(var_types type, GenTree* addr, GenTree* data, CORINFO_CLASS_HANDLE cls, unsigned size)
         : GenTreeBlk(GT_STORE_OBJ, type, addr, data, size), gtClass(cls)
     {
-        // By default, an OBJ is assumed to be a global reference.
-        gtFlags |= GTF_GLOB_REF;
-        noway_assert(cls != NO_CLASS_HANDLE);
-        _gtGcPtrCount = UINT32_MAX;
+        Init();
     }
 
 #if DEBUGGABLE_GENTREE