[Bug rtl-optimization/119171] [15 Regression] error: ‘asm’ operand has impossible constraints or there are not enough registers

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119171

--- Comment #3 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by H.J. Lu <hjl@gcc.gnu.org>:

https://gcc.gnu.org/g:06440e726acfa9c9695a07dc524a832a53057ad6

commit r15-7957-g06440e726acfa9c9695a07dc524a832a53057ad6
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Sun Mar 9 07:00:23 2025 -0700

    i386: Verify that argument registers are spilled properly

    While working on a local x86 patch, which passed the GCC testsuite, I got
    a compiler error:

    In function âparavirt_read_msrâ,
        inlined from âperf_ibs_handle_irqâ at
arch/x86/events/amd/ibs.c:1055:2:
    ./arch/x86/include/asm/paravirt_types.h:397:17: error: âasmâ operand
has impossible constraints or there are not enough registers
      397 |                 asm volatile(ALTERNATIVE(PARAVIRT_CALL,
ALT_CALL_INSTR, \
          |                 ^~~

    when building x86-64 Linux kernel.  RDI, RSI, RDX and RCX registers are
    used to pass arguments in 64-bit mode.  EAX, EDX and ECX registers are
    used to pass arguments in 32-bit mode.  But there is no coverage in the
    GCC testsuite.  Add tests to verify that argument registers are spilled
    properly.

            PR target/119171
            * gcc.target/i386/pr119171-1.c: New test.
            * gcc.target/i386/pr119171-2.c: Likewise.

    Signed-off-by: H.J. Lu <hjl.tools@gmail.com>