[Bug gas/11974] New: windows x86_64 sign extension

[muller at ics dot u-strasbg dot fr]

The parser for windows x86_64 does sign extensions
on values from 0x80000000 to 0xffffffff
even for constant 64-bit values.

  Even if 32-bit is the norm for constant expressions,
at least MOVABS instruction is supposed to accept 64-bit immediate values,
but the sign extension mechanism is still applied in that case.
  This happens in config/tc-i386.c
in i386_finalize_immediate.
  Linux assembler is not affected as
  `use_rela_relocations' variable is set to 1
for 64 bit ELF target objects.
  This creates incompatible output from a single assembler source.


>>>> Example <<<<<<<

>>>> source file: test-sign.s <<<<<<<
        .data
test:
        .quad 0

        .text
        .global _settest1
_settest1:
        movq    $0x80000001,%rax
        movq    %rax,test
        retq

        .global _settest2
_settest2:
        movq    $0x180000001,%rax
        movq    %rax,test
        retq

        .global _gettest
_gettest:
        movq    test,%rax
        retq

        .global _test_push_imm
_test_push_imm:
        pushq   %rbp
        movq    %rsp,%rbp
        pushq   $0x80000001
        movq    -8(%rbp),%rax
        movq    %rax,test
        leaveq
        retq

        .global _settestmovabs
_settestmovabs:
        movabsq $0x80000001,%rax
        retq
>>>> End of source <<<<<<<
>>>> Source file test.c <<<<<<<
#include <stdio.h>

extern void settest1 ();
extern void settest2 ();
extern void settestmovabs ();

extern long long int gettest ();

int
main ()
{
  long long int res;
  res = gettest ();
  if (res != 0)
    printf ("Error for value 0\n");
  settest2 ();
  res = gettest ();
  if (res != (long long int) (0x180000001))
    printf ("Error for value 0x180000001\n");
  settest1 ();
  res = gettest ();
  if (res != (long long int) (0x80000001))
    printf ("Error for value 0x80000001\n");
  settestmovabs ();
  res = gettest ();
  if (res != (long long int) (0x80000001))
    printf ("Error for value 0x80000001\n");
  return 0;
}
>>>> End of source <<<<<<<

Assemble sign-test.s using GNU as for x86_64 windows

as -o test-sign.o test-sign.s

Compile test.c:

gcc -o test.exe test-sign.o test.c

Run ./test.exe:

$ ./test
Error for value 0x80000001 with settest1
Error for value 0x80000001 with settestmovabs

-- 
           Summary: windows x86_64 sign extension
           Product: binutils
           Version: 2.21 (HEAD)
            Status: NEW
          Severity: normal
          Priority: P2
         Component: gas
        AssignedTo: unassigned at sources dot redhat dot com
        ReportedBy: muller at ics dot u-strasbg dot fr
                CC: bug-binutils at gnu dot org
  GCC host triplet: x86_64-w64-mingw32


http://sourceware.org/bugzilla/show_bug.cgi?id=11974

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