[Bug gas/29183] New: Inconsistent behaviors of Types with PTR operator

[j3r3miasmg at gmail dot com]

https://sourceware.org/bugzilla/show_bug.cgi?id=29183

            Bug ID: 29183
           Summary: Inconsistent behaviors of Types with PTR operator
           Product: binutils
           Version: 2.38
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: gas
          Assignee: unassigned at sourceware dot org
          Reporter: j3r3miasmg at gmail dot com
  Target Milestone: ---

Component: GAS
OS: Linux

The lack of PTR operator when any type is used generates a unexpected result.

Example code:
.global _start
.intel_syntax noprefix
_start:
    mov  al, [rdi]
    mov eax, [rdi]
    mov rax, [rdi]

    mov  al, BYTE  [rdi]
    mov eax, DWORD [rdi]
    mov rax, QWORD [rdi]

    mov  al, BYTE  PTR [rdi]
    mov eax, DWORD PTR [rdi]
    mov rax, QWORD PTR [rdi]

    mov  al, BYTE 
    mov eax, DWORD 
    mov rax, QWORD

Objdump output:
0000000000000000 <_start>:
   0:  8a 07                  mov    al,BYTE PTR [rdi]
   2:  8b 07                  mov    eax,DWORD PTR [rdi]
   4:  48 8b 07               mov    rax,QWORD PTR [rdi]
   7:  8a 47 01               mov    al,BYTE PTR [rdi+0x1]
   a:  8b 47 04               mov    eax,DWORD PTR [rdi+0x4]
   d:  48 8b 47 08            mov    rax,QWORD PTR [rdi+0x8]
  11:  8a 07                  mov    al,BYTE PTR [rdi]
  13:  8b 07                  mov    eax,DWORD PTR [rdi]
  15:  48 8b 07               mov    rax,QWORD PTR [rdi]
  18:  b0 01                  mov    al,0x1
  1a:  b8 04 00 00 00         mov    eax,0x4
  1f:  48 c7 c0 08 00 00 00   mov    rax,0x8

Using `mov eax, DWORD [rdi]` as and example, it could be seen that when DWORD
is used but PTR is not, instruction result includes an offset of 4 bytes to the
source address, and the result in instruction 0xa of the objdump: `mov   
eax,DWORD PTR [rdi+0x4]`. This behavior is different from instructions 0x2 and
0x13 of the obdjump when I believe it should not be.

This occurs because BYTE, WORD, DWORD and QWORD can be used as defines to 1, 2,
4 and 8 (check lines 0x18, 0x1a and 0x1f of objdump) and `mov eax, DWORD [rdi]`
is the same as `mov eax, 4[rdi]` and also equals to `mov eax, [rdi + 4]`.

Build Date & Hardware: binutils-2_38 Feb 9 - Ubuntu 20.04.4 LTS

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