Replace array type handle with method table in arguments of array allocation helpers (#12369)

* Remove direct usage of type handle in JIT_NewArr1, with except of retrieving template method table.

* Assert that array type descriptor is loaded when array object's method table is set.

* Pass template method tables instead of array type descriptors to array allocation helpers.

1 files changed, 9 insertions, 30 deletions

diff --git a/src/vm/amd64/JitHelpers_InlineGetThread.asm b/src/vm/amd64/JitHelpers_InlineGetThread.asm
index 700c3b393c..022ec675df 100644
--- a/src/vm/amd64/JitHelpers_InlineGetThread.asm
+++ b/src/vm/amd64/JitHelpers_InlineGetThread.asm
@@ -147,15 +147,6 @@ align 16
         jmp     JIT_Box
 NESTED_END JIT_BoxFastMP_InlineGetThread, _TEXT
 
-FIX_INDIRECTION macro Reg
-ifdef FEATURE_PREJIT
-        test    Reg, 1
-        jz      @F
-        mov     Reg, [Reg-1]
-    @@:
-endif
-endm
-
 LEAF_ENTRY AllocateStringFastMP_InlineGetThread, _TEXT
         ; We were passed the number of characters in ECX
 
@@ -203,10 +194,9 @@ endif ; _DEBUG
         jmp     FramedAllocateString
 LEAF_END AllocateStringFastMP_InlineGetThread, _TEXT
 
-; HCIMPL2(Object*, JIT_NewArr1, CORINFO_CLASS_HANDLE arrayTypeHnd_, INT_PTR size)
+; HCIMPL2(Object*, JIT_NewArr1VC_MP_InlineGetThread, CORINFO_CLASS_HANDLE arrayMT, INT_PTR size)
 LEAF_ENTRY JIT_NewArr1VC_MP_InlineGetThread, _TEXT
-        ; We were passed a type descriptor in RCX, which contains the (shared)
-        ; array method table and the element type.
+        ; We were passed a (shared) method table in RCX, which contains the element type.
 
         ; The element count is in RDX
 
@@ -223,17 +213,12 @@ LEAF_ENTRY JIT_NewArr1VC_MP_InlineGetThread, _TEXT
 
         ; In both cases we do a final overflow check after adding to the alloc_ptr.
 
-        ; we need to load the true method table from the type desc
-        mov     r9, [rcx + OFFSETOF__ArrayTypeDesc__m_TemplateMT - 2]
-        
-        FIX_INDIRECTION r9
-
         cmp     rdx, (65535 - 256)
         jae     OversizedArray
 
-        movzx   r8d, word ptr [r9 + OFFSETOF__MethodTable__m_dwFlags]  ; component size is low 16 bits
+        movzx   r8d, word ptr [rcx + OFFSETOF__MethodTable__m_dwFlags]  ; component size is low 16 bits
         imul    r8d, edx
-        add     r8d, dword ptr [r9 + OFFSET__MethodTable__m_BaseSize] 
+        add     r8d, dword ptr [rcx + OFFSET__MethodTable__m_BaseSize]
 
         ; round the size to a multiple of 8
 
@@ -252,7 +237,7 @@ LEAF_ENTRY JIT_NewArr1VC_MP_InlineGetThread, _TEXT
         ja      AllocFailed
 
         mov     [r11 + OFFSET__Thread__m_alloc_context__alloc_ptr], r8
-        mov     [rax], r9
+        mov     [rax], rcx
 
         mov     dword ptr [rax + OFFSETOF__ArrayBase__m_NumComponents], edx
 
@@ -268,10 +253,9 @@ endif ; _DEBUG
 LEAF_END JIT_NewArr1VC_MP_InlineGetThread, _TEXT
 
 
-; HCIMPL2(Object*, JIT_NewArr1, CORINFO_CLASS_HANDLE arrayTypeHnd_, INT_PTR size)
+; HCIMPL2(Object*, JIT_NewArr1OBJ_MP_InlineGetThread, CORINFO_CLASS_HANDLE arrayMT, INT_PTR size)
 LEAF_ENTRY JIT_NewArr1OBJ_MP_InlineGetThread, _TEXT
-        ; We were passed a type descriptor in RCX, which contains the (shared)
-        ; array method table and the element type.
+        ; We were passed a (shared) method table in RCX, which contains the element type.
 
         ; The element count is in RDX
 
@@ -285,16 +269,11 @@ LEAF_ENTRY JIT_NewArr1OBJ_MP_InlineGetThread, _TEXT
         cmp     rdx, (ASM_LARGE_OBJECT_SIZE - 256)/8 ; sizeof(void*)
         jae     OversizedArray
 
-        ; we need to load the true method table from the type desc
-        mov     r9, [rcx + OFFSETOF__ArrayTypeDesc__m_TemplateMT - 2]
-        
-        FIX_INDIRECTION r9
-
         ; In this case we know the element size is sizeof(void *), or 8 for x64
         ; This helps us in two ways - we can shift instead of multiplying, and
         ; there's no need to align the size either
 
-        mov     r8d, dword ptr [r9 + OFFSET__MethodTable__m_BaseSize]
+        mov     r8d, dword ptr [rcx + OFFSET__MethodTable__m_BaseSize]
         lea     r8d, [r8d + edx * 8]
 
         ; No need for rounding in this case - element size is 8, and m_BaseSize is guaranteed
@@ -310,7 +289,7 @@ LEAF_ENTRY JIT_NewArr1OBJ_MP_InlineGetThread, _TEXT
         ja      AllocFailed
 
         mov     [r11 + OFFSET__Thread__m_alloc_context__alloc_ptr], r8
-        mov     [rax], r9
+        mov     [rax], rcx
 
         mov     dword ptr [rax + OFFSETOF__ArrayBase__m_NumComponents], edx