On Mon, May 18, 2026 at 6:21 AM H.J. Lu <[email protected]> wrote:
>
> On Sun, May 17, 2026 at 7:57 PM oltolm <[email protected]> wrote:
> >
> > From: Oleg Tolmatcev <[email protected]>
> >
> > The preserve_none calling convention uses the six-register preserve_none
> > integer parameter set even when the default ABI is MS. Update argument
> > register recognition, cumulative argument setup, and argument lowering so
> > preserve_none calls on x86_64 MinGW use the generic 64-bit path rather than
> > the plain MS ABI path.
> >
> > Add MinGW compile tests for integer argument remapping and sibling-call
> > behavior.
> > Update scanasm matching for MinGW.
> >
> > gcc/config/i386/ChangeLog:
> >
> > * i386.cc (ix86_function_arg_regno_p): Use six integer argument
> > registers for preserve_none under the MS ABI.
> > (init_cumulative_args): Likewise.
> > (ix86_function_arg): Route preserve_none calls through
> > function_arg_64.
> >
> > gcc/testsuite/ChangeLog:
> >
> > * gcc.target/i386/preserve-none-31.c: New test.
> > * gcc.target/i386/preserve-none-32.c: New test.
> > * lib/scanasm.exp (configure_check-function-bodies): Handle x86_64
> > MinGW end markers and instruction indentation.
> >
> > Signed-off-by: oltolm <[email protected]>
> > ---
> > gcc/config/i386/i386.cc | 19 +++++++-----
> > .../gcc.target/i386/preserve-none-31.c | 30 +++++++++++++++++++
> > .../gcc.target/i386/preserve-none-32.c | 24 +++++++++++++++
> > gcc/testsuite/lib/scanasm.exp | 16 ++++++----
> > 4 files changed, 76 insertions(+), 13 deletions(-)
> > create mode 100644 gcc/testsuite/gcc.target/i386/preserve-none-31.c
> > create mode 100644 gcc/testsuite/gcc.target/i386/preserve-none-32.c
> >
> > diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc
> > index 2744c74957..9bb6b6001c 100644
> > --- a/gcc/config/i386/i386.cc
> > +++ b/gcc/config/i386/i386.cc
> > @@ -1609,8 +1609,13 @@ ix86_function_arg_regno_p (int regno)
> > else
> > parm_regs = x86_64_int_parameter_registers;
> >
> > - for (i = 0; i < (call_abi == MS_ABI
> > - ? X86_64_MS_REGPARM_MAX : X86_64_REGPARM_MAX); i++)
> > + int regparm_max
> > + = (call_abi == MS_ABI
> > + && !(cfun && cfun->machine->call_saved_registers ==
> > TYPE_PRESERVE_NONE))
> > + ? X86_64_MS_REGPARM_MAX
> > + : X86_64_REGPARM_MAX;
> > + for (i = 0; i < regparm_max; i++)
> > if (regno == parm_regs[i])
> > return true;
> > return false;
> > @@ -1920,9 +1925,9 @@ init_cumulative_args (CUMULATIVE_ARGS *cum, /*
> > Argument info to initialize */
> > cum->nregs = ix86_regparm;
> > if (TARGET_64BIT)
> > {
> > - cum->nregs = (cum->call_abi == SYSV_ABI
> > - ? X86_64_REGPARM_MAX
> > - : X86_64_MS_REGPARM_MAX);
> > + cum->nregs = (cum->preserve_none_abi || cum->call_abi == SYSV_ABI
> > + ? X86_64_REGPARM_MAX
> > + : X86_64_MS_REGPARM_MAX);
> > }
> > if (TARGET_SSE)
> > {
> > @@ -3273,7 +3278,7 @@ ix86_function_arg_advance (cumulative_args_t cum_v,
> > {
> > enum calling_abi call_abi = cum ? cum->call_abi : ix86_abi;
> >
> > - if (call_abi == MS_ABI)
> > + if (call_abi == MS_ABI && !(cum && cum->preserve_none_abi))
> > nregs = function_arg_advance_ms_64 (cum, bytes, words);
> > else
> > nregs = function_arg_advance_64 (cum, mode, arg.type, words,
> > @@ -3604,7 +3609,7 @@ ix86_function_arg (cumulative_args_t cum_v, const
> > function_arg_info &arg)
> > {
> > enum calling_abi call_abi = cum ? cum->call_abi : ix86_abi;
> >
> > - if (call_abi == MS_ABI)
> > + if (call_abi == MS_ABI && !(cum && cum->preserve_none_abi))
> > reg = function_arg_ms_64 (cum, mode, arg.mode, arg.named,
> > arg.type, bytes);
> > else
> > diff --git a/gcc/testsuite/gcc.target/i386/preserve-none-31.c
> > b/gcc/testsuite/gcc.target/i386/preserve-none-31.c
> > new file mode 100644
> > index 0000000000..d8ab38cdba
> > --- /dev/null
> > +++ b/gcc/testsuite/gcc.target/i386/preserve-none-31.c
> > @@ -0,0 +1,30 @@
> > +/* { dg-do compile { target { x86_64-*-mingw* } } } */
>
> Remove { target { x86_64-*-mingw* } }.
Please use { target lp64 }.
> > +/* { dg-options "-O2 -msse2 -mno-apxf" } */
>
> Add -mabi=ms instead.
>
> > +/* { dg-final { check-function-bodies "**" "" "" { target "*-*-*" } } } */
>
> { target lp64 }
>
> > +
> > +/*
> > +**entry:
> > +** subq \$72, %rsp
> > +** xorl %eax, %eax
> > +** movl 120\(%rsp\), %esi
> > +** movl 112\(%rsp\), %edi
> > +** movl %ecx, %r12d
> > +** movl %edx, %r13d
> > +** movl %r9d, %r15d
> > +** movl %r8d, %r14d
> > +** movl \$-559038737, 48\(%rsp\)
> > +** call continuation
> > +** nop
> > +** addq \$72, %rsp
> > +** ret
> > +*/
> > +
> > +extern void continuation (int, int, int, int, int, int, ...)
> > + __attribute__ ((preserve_none));
> > +
> > +__attribute__ ((no_callee_saved_registers))
> > +void
> > +entry (int arg1, int arg2, int arg3, int arg4, int arg5, int arg6)
> > +{
> > + continuation (arg1, arg2, arg3, arg4, arg5, arg6, 0xdeadbeef);
> > +}
>
> Please also test -mabi=ms with sysv_abi attribute and -mabi=sysv
> with ms_abi attribute.
>
> > diff --git a/gcc/testsuite/gcc.target/i386/preserve-none-32.c
> > b/gcc/testsuite/gcc.target/i386/preserve-none-32.c
> > new file mode 100644
> > index 0000000000..8a2173b413
> > --- /dev/null
> > +++ b/gcc/testsuite/gcc.target/i386/preserve-none-32.c
> > @@ -0,0 +1,24 @@
> > +/* { dg-do compile { target { x86_64-*-mingw* } } } */
> > +/* { dg-options "-O2 -msse2 -mno-apxf" } */
> > +/* { dg-final { check-function-bodies "**" "" "" { target "*-*-*" } } } */
> > +
> > +/*
> > +**entry:
> > +** movl 56\(%rsp\), %esi
> > +** movl 48\(%rsp\), %edi
> > +** movl 40\(%rsp\), %r15d
> > +** movl %edx, %r12d
> > +** movl %r9d, %r14d
> > +** movl %r8d, %r13d
> > +** jmp continuation
> > +*/
> > +
> > +extern void continuation (double, int, int, int, int, int, int)
> > + __attribute__ ((preserve_none));
> > +
> > +__attribute__ ((no_callee_saved_registers))
> > +void
> > +entry (double fp, int arg1, int arg2, int arg3, int arg4, int arg5, int
> > arg6)
> > +{
> > + continuation (fp, arg1, arg2, arg3, arg4, arg5, arg6);
> > +}
> > diff --git a/gcc/testsuite/lib/scanasm.exp b/gcc/testsuite/lib/scanasm.exp
> > index abfdd6a3a1..52f03e4412 100644
> > --- a/gcc/testsuite/lib/scanasm.exp
> > +++ b/gcc/testsuite/lib/scanasm.exp
>
> I don't think this change is required. You can use
>
> **...
>
> to skip unrelated lines.
>
> > @@ -4,12 +4,12 @@
> > # it under the terms of the GNU General Public License as published by
> > # the Free Software Foundation; either version 3 of the License, or
> > # (at your option) any later version.
> > -#
> > +#
> > # This program is distributed in the hope that it will be useful,
> > # but WITHOUT ANY WARRANTY; without even the implied warranty of
> > # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> > # GNU General Public License for more details.
> > -#
> > +#
> > # You should have received a copy of the GNU General Public License
> > # along with GCC; see the file COPYING3. If not see
> > # <http://www.gnu.org/licenses/>.
> > @@ -138,7 +138,7 @@ proc scan-assembler-not { args } {
> >
> > set_required_options_for scan-assembler-not
> >
> > -# Return the scan for the assembly for hidden visibility.
> > +# Return the scan for the assembly for hidden visibility.
> >
> > proc hidden-scan-for { symbol } {
> >
> > @@ -563,7 +563,7 @@ proc scan-assembler-times { args } {
> >
> > set_required_options_for scan-assembler-times
> >
> > -# Call pass if pattern is present within a lower or upper bound,
> > +# Call pass if pattern is present within a lower or upper bound,
> > # otherwise fail.
> > # ex /* { dg-final { scan-assembler-bound {RE} > 3 } }
> > proc scan-assembler-bound { args } {
> > @@ -610,7 +610,7 @@ proc scan-assembler-bound { args } {
> > error "scan-assembler-bound: illegal argument: $bound"
> > return
> > }
> > -
> > +
> > set fd [open $output_file r]
> > set text [read $fd]
> > close $fd
> > @@ -932,7 +932,8 @@ proc configure_check-function-bodies { config } {
> > set up_config(end) {^\}$}
> > } elseif { [istarget *-*-darwin*] } {
> > set up_config(end) {^LFE[0-9]+}
> > - } elseif { [istarget aarch64*-*-mingw32] } {
> > + } elseif { [istarget aarch64*-*-mingw32]
> > + || [istarget x86_64*-*-mingw*] } {
> > set up_config(end) {seh_endproc}
> > } else {
> > set up_config(end) {^\s*\.size}
> > @@ -964,6 +965,9 @@ proc configure_check-function-bodies { config } {
> > # any whitespace prefixed, and we'd like to be able to match these,
> > # too. We thereare expect any amount of whitespace here.
> > set up_config(line_prefix) {\t*}
> > + } elseif { [istarget *-*-mingw*] } {
> > + # MinGW assemblers may indent instructions with spaces rather than
> > tabs.
> > + set up_config(line_prefix) {[ \t]+}
> > } else {
> > set up_config(line_prefix) {\t}
> > }
> > --
> > 2.54.0.windows.1
> >
>
>
> --
> H.J.
--
H.J.
