[Bug c/111237] New: fp-int-convert-float64x.c fails on x86_64-apple-darwin with "ambiguous instructions require an explicit suffix"

[fxcoudert at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111237

            Bug ID: 111237
           Summary: fp-int-convert-float64x.c fails on x86_64-apple-darwin
                    with "ambiguous instructions require an explicit
                    suffix"
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: fxcoudert at gcc dot gnu.org
  Target Milestone: ---

Many of these messages:

/var/folders/h8/9hx_fyj91053ksgdzb2w03vw0000gp/T//ccO1vBzR.s:16:2: error:
ambiguous instructions require an explicit suffix (could be 'filds', or
'fildl')
        fild    -8(%rbp)
        ^
/var/folders/h8/9hx_fyj91053ksgdzb2w03vw0000gp/T//ccO1vBzR.s:19:2: error:
ambiguous instructions require an explicit suffix (could be 'fisttps', or
'fisttpl')
        fisttp  -8(%rbp)
        ^


This is on a cross-compiler from aarch64-apple-darwin22 to
x86_64-apple-darwin22, but I think it would be the same on a native compiler.


Short reproducer:

$ cat toto.c 
int main(void)
{
  unsigned char ivin;
  unsigned char ivout;
  _Float64x fv1;
  _Float64x fv2;

  ivin = 0;
  fv1 = 0;
  fv2 = (_Float64x) ivin;
  ivout = (unsigned char) fv1;
}
$ ./bin/x86_64-apple-darwin22-gcc toto.c -c
/var/folders/h8/9hx_fyj91053ksgdzb2w03vw0000gp/T//ccn0Y3rC.s:14:2: error:
ambiguous instructions require an explicit suffix (could be 'filds', or
'fildl')
        fild    -66(%rbp)
        ^
/var/folders/h8/9hx_fyj91053ksgdzb2w03vw0000gp/T//ccn0Y3rC.s:17:2: error:
ambiguous instructions require an explicit suffix (could be 'fisttps', or
'fisttpl')
        fisttp  -66(%rbp)
        ^
$ ./bin/x86_64-apple-darwin22-gcc toto.c -S
$ cat toto.s 
        .text
        .globl _main
_main:
LFB0:
        pushq   %rbp
LCFI0:
        movq    %rsp, %rbp
LCFI1:
        movb    $0, -1(%rbp)
        fldz
        fstpt   -32(%rbp)
        movzbl  -1(%rbp), %eax
        movw    %ax, -66(%rbp)
        fild    -66(%rbp)
        fstpt   -48(%rbp)
        fldt    -32(%rbp)
        fisttp  -66(%rbp)
        movzwl  -66(%rbp), %eax
        movb    %al, -49(%rbp)
        movl    $0, %eax
        popq    %rbp
LCFI2:
        ret
LFE0:
        .section
__TEXT,__eh_frame,coalesced,no_toc+strip_static_syms+live_support
EH_frame1:
        .set L$set$0,LECIE1-LSCIE1
        .long L$set$0
LSCIE1:
        .long   0
        .byte   0x1
        .ascii "zR\0"
        .byte   0x1
        .byte   0x78
        .byte   0x10
        .byte   0x1
        .byte   0x10
        .byte   0xc
        .byte   0x7
        .byte   0x8
        .byte   0x90
        .byte   0x1
        .align 3
LECIE1:
LSFDE1:
        .set L$set$1,LEFDE1-LASFDE1
        .long L$set$1
LASFDE1:
        .long   LASFDE1-EH_frame1
        .quad   LFB0-.
        .set L$set$2,LFE0-LFB0
        .quad L$set$2
        .byte   0
        .byte   0x4
        .set L$set$3,LCFI0-LFB0
        .long L$set$3
        .byte   0xe
        .byte   0x10
        .byte   0x86
        .byte   0x2
        .byte   0x4
        .set L$set$4,LCFI1-LCFI0
        .long L$set$4
        .byte   0xd
        .byte   0x6
        .byte   0x4
        .set L$set$5,LCFI2-LCFI1
        .long L$set$5
        .byte   0xc
        .byte   0x7
        .byte   0x8
        .align 3
LEFDE1:
        .ident  "GCC: (GNU) 14.0.0 20230830 (experimental)"
        .subsections_via_symbols


For the record, the assembler is called as:


"/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang"
-cc1as -triple x86_64-apple-macosx13.0.0 -filetype obj -main-file-name
ccImMDJg.s -target-cpu penryn -fdebug-compilation-dir=/tmp/irun
-dwarf-debug-producer "Apple clang version 14.0.3 (clang-1403.0.22.14.1)"
-dwarf-version=4 -mrelocation-model pic --mrelax-relocations -mllvm
-x86-pad-for-align=false -mllvm -disable-aligned-alloc-awareness=1 -o toto.o
/var/folders/h8/9hx_fyj91053ksgdzb2w03vw0000gp/T//ccImMDJg.s