1 files changed, 48 insertions, 0 deletions
diff --git a/deps/v8/src/heap/base/asm/ia32/push_registers_masm.asm b/deps/v8/src/heap/base/asm/ia32/push_registers_masm.asm
new file mode 100644
index 0000000000..a35fd6e527
--- /dev/null
+++ b/deps/v8/src/heap/base/asm/ia32/push_registers_masm.asm
@@ -0,0 +1,48 @@
+;; Copyright 2020 the V8 project authors. All rights reserved.
+;; Use of this source code is governed by a BSD-style license that can be
+;; found in the LICENSE file.
+
+;; MASM syntax
+;; https://docs.microsoft.com/en-us/cpp/assembler/masm/microsoft-macro-assembler-reference?view=vs-2019
+
+.model flat, C
+
+public PushAllRegistersAndIterateStack
+
+.code
+PushAllRegistersAndIterateStack:
+    ;; Push all callee-saved registers to get them on the stack for conservative
+    ;; stack scanning.
+    ;;
+    ;; We maintain 16-byte alignment at calls. There is an 8-byte return address
+    ;; on the stack and we push 72 bytes which maintains 16-byte stack alignment
+    ;; at the call.
+    ;;
+    ;; The following assumes cdecl calling convention.
+    ;; Source: https://docs.microsoft.com/en-us/cpp/cpp/cdecl?view=vs-2019
+    ;;
+    ;; [ IterateStackCallback ]
+    ;; [ StackVisitor*        ]
+    ;; [ Stack*               ]
+    ;; [ ret                  ]
+    push ebp
+    mov ebp, esp
+    push ebx
+    push esi
+    push edi
+    ;; Save 3rd parameter (IterateStackCallback).
+    mov ecx, [ esp + 28 ]
+    ;; Pass 3rd parameter as esp (stack pointer).
+    push esp
+    ;; Pass 2nd parameter (StackVisitor*).
+    push [ esp + 28 ]
+    ;; Pass 1st parameter (Stack*).
+    push [ esp + 28 ]
+    call ecx
+    ;; Pop the callee-saved registers.
+    add esp, 24
+    ;; Restore rbp as it was used as frame pointer.
+    pop ebp
+    ret
+
+end