Implement invokeNative asm code for MinGW (#1753)

And update the document of building iwasm for MinGW.

core/iwasm/common/arch/invokeNative_mingw_x64.s

@@ -0,0 +1,57 @@
+# Copyright (C) 2019 Intel Corporation.  All rights reserved.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+.text
+.align 2
+.globl invokeNative
+invokeNative:
+
+    # %rcx func_ptr
+    # %rdx argv
+    # %r8 n_stacks
+
+    push %rbp
+    mov %rsp, %rbp
+
+    mov %rcx, %r10    # func_ptr
+    mov %rdx, %rax    # argv
+    mov %r8, %rcx     # n_stacks
+
+    # fill all fp args
+    movsd 0(%rax), %xmm0
+    movsd 8(%rax), %xmm1
+    movsd 16(%rax), %xmm2
+    movsd 24(%rax), %xmm3
+
+    # check for stack args
+    cmp $0, %rcx
+    jz cycle_end
+
+    mov %rsp, %rdx
+    and $15, %rdx
+    jz no_abort
+    int $3
+no_abort:
+    mov %rcx, %rdx
+    and $1, %rdx
+    shl $3, %rdx
+    sub %rdx, %rsp
+
+    # store stack args
+    lea 56(%rax, %rcx, 8), %r9
+    sub %rsp, %r9                   # offset
+cycle:
+    push (%rsp, %r9)
+    loop cycle
+
+cycle_end:
+    mov 32(%rax), %rcx
+    mov 40(%rax), %rdx
+    mov 48(%rax), %r8
+    mov 56(%rax), %r9
+
+    sub $32, %rsp # shadow space
+
+    call *%r10
+    leave
+    ret

core/iwasm/common/arch/invokeNative_mingw_x64_simd.s

@@ -0,0 +1,57 @@
+# Copyright (C) 2019 Intel Corporation.  All rights reserved.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+.text
+.align 2
+.globl invokeNative
+invokeNative:
+
+    # %rcx func_ptr
+    # %rdx argv
+    # %r8 n_stacks
+
+    push %rbp
+    mov %rsp, %rbp
+
+    mov %rcx, %r10    # func_ptr
+    mov %rdx, %rax    # argv
+    mov %r8, %rcx     # n_stacks
+
+    # fill all fp args
+    movdqu 0(%rax), %xmm0
+    movdqu 16(%rax), %xmm1
+    movdqu 32(%rax), %xmm2
+    movdqu 48(%rax), %xmm3
+
+    # check for stack args
+    cmp $0, %rcx
+    jz cycle_end
+
+    mov %rsp, %rdx
+    and $15, %rdx
+    jz no_abort
+    int $3
+no_abort:
+    mov %rcx, %rdx
+    and $1, %rdx
+    shl $3, %rdx
+    sub %rdx, %rsp
+
+    # store stack args
+    lea 88(%rax, %rcx, 8), %r9
+    sub %rsp, %r9                   # offset
+cycle:
+    push (%rsp, %r9)
+    loop cycle
+
+cycle_end:
+    mov 64(%rax), %rcx
+    mov 72(%rax), %rdx
+    mov 80(%rax), %r8
+    mov 88(%rax), %r9
+
+    sub $32, %rsp # shadow space
+
+    call *%r10
+    leave
+    ret