On Thu, May 15, 2025 at 12:34 PM Dimitar Dimitrov <dimi...@dinux.eu> wrote: > > After r16-160-ge6f89d78c1a752, late_combine2 started transforming the > following RTL for pru-unknown-elf: > > (insn 3949 3948 3951 255 (set (reg:QI 56 r14.b0 [orig:1856 _619 ] [1856]) > (and:QI (reg:QI 1 r0.b1 [orig:1855 _201 ] [1855]) > (const_int 3 [0x3]))) > (nil)) > ... > (insn 3961 7067 3962 255 (set (reg:SI 56 r14.b0) > (zero_extend:SI (reg:QI 56 r14.b0 [orig:1856 _619 ] [1856]))) > (nil)) > > into: > > (insn 3961 7067 3962 255 (set (reg:SI 56 r14.b0) > (and:SI (subreg:SI (reg:QI 1 r0.b1 [orig:1855 _201 ] [1855]) 0) > (const_int 3 [0x3]))) > (nil)) > > That caused libbacktrace build to break for pru-unknown-elf. Register > r0.b1 (regno 1) is not valid for SImode, which validate_subreg failed to > reject. > > Fix by calling HARD_REGNO_MODE_OK to ensure that both inner and outer > modes are valid for the hardware subreg. > > This patch fixes the broken PRU toolchain build. It leaves only two > test case regressions for PRU, caused by rnreg pass renaming a valid > paradoxical subreg into an invalid one. > gcc.c-torture/execute/20040709-1.c > gcc.c-torture/execute/20040709-2.c > > PR target/119966 > > gcc/ChangeLog: > > * emit-rtl.cc (validate_subreg): Validate inner > and outer mode for paradoxical hardware subregs. > > Co-authored-by: Andrew Pinski <pins...@gmail.com>
Note this should be `Andrew Pinski <quic_apin...@quicinc.com>` for legal requirements. Thanks, Andrew > Signed-off-by: Dimitar Dimitrov <dimi...@dinux.eu> > --- > gcc/emit-rtl.cc | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/gcc/emit-rtl.cc b/gcc/emit-rtl.cc > index e46b0f9eac4..6c5d9b55508 100644 > --- a/gcc/emit-rtl.cc > +++ b/gcc/emit-rtl.cc > @@ -983,6 +983,9 @@ validate_subreg (machine_mode omode, machine_mode imode, > if ((COMPLEX_MODE_P (imode) || VECTOR_MODE_P (imode)) > && GET_MODE_INNER (imode) == omode) > ; > + else if (!targetm.hard_regno_mode_ok (regno, imode) > + || !targetm.hard_regno_mode_ok (regno, omode)) > + return false; > else if (!REG_CAN_CHANGE_MODE_P (regno, imode, omode)) > return false; > > -- > 2.49.0 >
