[Bug target/100782] New: [11 Regression] sh4 ICEs on -O2 -fPIE -fstack-protector: internal compiler error: in curr_insn_transform, at lra-constraints.c:4132

[Bug target/100782] New: [11 Regression] sh4 ICEs on -O2 -fPIE -fstack-protector: internal compiler error: in curr_insn_transform, at lra-constraints.c:4132

[slyfox at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100782

            Bug ID: 100782
           Summary: [11 Regression] sh4 ICEs on -O2 -fPIE
                    -fstack-protector: internal compiler error: in
                    curr_insn_transform, at lra-constraints.c:4132
           Product: gcc
           Version: 11.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: slyfox at gcc dot gnu.org
  Target Milestone: ---
              Host: x86_64-pc-linux-gnu
            Target: sh4-unknown-linux-gnu
             Build: x86_64-pc-linux-gnu

Not sure if it's a dupe of bug #100241. Filing just in case.

Observed when built libffi for sh4 target. Minimal example:

// cat raw_api.c.c
void ffi_raw_to_ptrarray(void);
int ffi_call(void (*)(void *, void *), void*, void*, void*);

void ffi_raw_call_cif(void *fn, void *rvalue) {
  void *avalue = __builtin_alloca(sizeof 0);
  ffi_raw_to_ptrarray();
  ffi_call(ffi_raw_call_cif, fn, rvalue, avalue);
}

$ ./xgcc -B. -O2 -mlra -fexceptions -fPIE -fstack-protector -c raw_api.c.c -o
raw_api.o

raw_api.c.c: In function 'ffi_raw_call_cif':
raw_api.c.c:8:1: error: unable to generate reloads for:
    8 | }
      | ^
(call_insn 18 16 20 2 (parallel [
            (call (mem:SI (symbol_ref:SI ("ffi_raw_to_ptrarray") [flags 0x41]
<function_decl 0x7fc7ae93bb00 ffi_raw_to_ptrarray>) [0 ffi_raw_to_ptrarray S4
A32])
                (const_int 0 [0]))
            (use (reg:SI 154 fpscr0))
            (use (reg:SI 12 r12))
            (clobber (reg:SI 146 pr))
            (clobber (reg:SI 183))
        ]) "raw_api.c.c":6:3 228 {call_pcrel}
     (expr_list:REG_CALL_DECL (symbol_ref:SI ("ffi_raw_to_ptrarray") [flags
0x41] <function_decl 0x7fc7ae93bb00 ffi_raw_to_ptrarray>)
        (nil))
    (nil))
during RTL pass: reload
raw_api.c.c:8:1: internal compiler error: in curr_insn_transform, at
lra-constraints.c:4132
0x7fc7aea9287c __libc_start_main
        ../csu/libc-start.c:332
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.

Using built-in specs.
COLLECT_GCC=./xgcc
Target: sh4-unknown-linux-gnu
Configured with: ../gcc/configure --build=x86_64-pc-linux-gnu
--host=x86_64-pc-linux-gnu --target=sh4-unknown-linux-gnu
--prefix=/home/slyfox/dev/git/gcc-sh4-ice/../gcc-sh4-installed
--with-sysroot=/usr/sh4-unknown-linux-gnu --disable-bootstrap
--enable-languages=c --disable-nls CFLAGS=-O0 CXXFLAGS=-O0
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 12.0.0 20210526 (experimental) (GCC)

[Bug target/100782] [11 Regression] sh4 ICEs on -O2 -fPIE -fstack-protector: internal compiler error: in curr_insn_transform, at lra-constraints.c:4132

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100782

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |11.2

[Bug target/100782] [11 Regression] sh4 ICEs on -O2 -fPIE -fstack-protector: internal compiler error: in curr_insn_transform, at lra-constraints.c:4132

[slyfox at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100782

--- Comment #1 from Sergei Trofimovich <slyfox at gcc dot gnu.org> ---
(In reply to Sergei Trofimovich from comment #0)
> Not sure if it's a dupe of bug #100241. Filing just in case.

Probably different: it's a different target and different instruction.

[Bug target/100782] [11 Regression] sh4 ICEs on -O2 -fPIE -fstack-protector: internal compiler error: in curr_insn_transform, at lra-constraints.c:4132

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100782

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |WAITING
   Last reconfirmed|                            |2021-07-06
     Ever confirmed|0                           |1

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
The description says:

gcc version 12.0.0 20210526 (experimental) (GCC)

so is this about GCC 12 or GCC 11?  What version worked fine (why's this marked
as regression?)

[Bug target/100782] [11 Regression] sh4 ICEs on -O2 -fPIE -fstack-protector: internal compiler error: in curr_insn_transform, at lra-constraints.c:4132

[slyfox at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100782

--- Comment #3 from Sergei Trofimovich <slyfox at gcc dot gnu.org> ---
(In reply to Richard Biener from comment #2)
> The description says:
> 
> gcc version 12.0.0 20210526 (experimental) (GCC)
> 
> so is this about GCC 12 or GCC 11?  What version worked fine (why's this
> marked as regression?)

My apologies. It should be a gcc-11 regression. More gcc versions outputs:

$ /tmp:sh4-unknown-linux-gnu-gcc-10.3.0 -O2 -mlra -fexceptions -fPIE
-fstack-protector -c a.c
<ok>

$ sh4-unknown-linux-gnu-gcc-11.1.0 -O2 -mlra -fexceptions -fPIE
-fstack-protector -c a.c
a.c: In function 'ffi_raw_call_cif':
a.c:9:1: error: unable to generate reloads for:
    9 | }
      | ^
(call_insn 18 16 20 2 (parallel [
            (call (mem:SI (symbol_ref:SI ("ffi_raw_to_ptrarray") [flags 0x41]
<function_decl 0x7f3c4e947b00 ffi_raw_to_ptrarray>) [0 ffi_raw_to_ptrarray S4
A32])
                (const_int 0 [0]))
            (use (reg:SI 154 fpscr0))
            (use (reg:SI 12 r12))
            (clobber (reg:SI 146 pr))
            (clobber (reg:SI 183))
        ]) "a.c":7:3 228 {call_pcrel}
     (expr_list:REG_CALL_DECL (symbol_ref:SI ("ffi_raw_to_ptrarray") [flags
0x41] <function_decl 0x7f3c4e947b00 ffi_raw_to_ptrarray>)
        (nil))
    (nil))
during RTL pass: reload
a.c:9:1: internal compiler error: in curr_insn_transform, at
lra-constraints.c:4138
0x7f3c4ea9e7ac __libc_start_main
        ../csu/libc-start.c:332
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <https://bugs.gentoo.org/> for instructions.

[Bug target/100782] [11 Regression] sh4 ICEs on -O2 -fPIE -fstack-protector: internal compiler error: in curr_insn_transform, at lra-constraints.c:4132

[slyfox at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100782

--- Comment #4 from Sergei Trofimovich <slyfox at gcc dot gnu.org> ---
Bisected down to r11-4577

commit 44fbc9c6e02ca5b8f98f25b514ed7588e7ba733d
Author: Vladimir N. Makarov <vmakarov@redhat.com>
Date:   Fri Oct 30 15:05:22 2020 -0400

    Take insn scratch RA requirements into account in IRA.

      The patch changes insn scratches which require registers for all
    insn alternatives (in other words w/o X constraint in scratch
    constraint string).  This is done before IRA staring its work.  LRA
    still continue to change the rest scratches (with X constraint and in
    insn created during IRA) into pseudos.  As before the patch at the end
    of LRA work, spilled scratch pseudos (for which X constraint was
    chosen) changed into scratches back.

[Bug target/100782] [11 Regression] sh4 ICEs on -O2 -fPIE -fstack-protector: internal compiler error: in curr_insn_transform, at lra-constraints.c:4132

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100782

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|11.2                        |11.3

--- Comment #5 from Richard Biener <rguenth at gcc dot gnu.org> ---
GCC 11.2 is being released, retargeting bugs to GCC 11.3

[Bug target/100782] [11 Regression] sh4 ICEs on -O2 -fPIE -fstack-protector: internal compiler error: in curr_insn_transform, at lra-constraints.c:4132

[slyfox at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100782

--- Comment #6 from Sergei Trofimovich <slyfox at gcc dot gnu.org> ---
Trying to understand why rejection happens: -fdump-rtl-all-slim 295r.reload
says:

         Choosing alt 0 in insn 12:  (0) =r  (1) %0  (2) rI08
{*addsi3_compact_lra}
            alt=0: No input/output reload -- refuse
         ...
         12: r15:SI=r15:SI-0x4

I'm surprised the same (hard) reg is used in source and destination in insn 12.

*addsi3_compact_lra hints at special assumptions about it:

;; The *addsi3_compact is made an insn_and_split and accepts actually
;; impossible constraints to make LRA's register elimination work well on SH.
;; The problem is that LRA expects something like
;;    (set rA (plus rB (const_int N)))
;; to work.  We can do that, but we have to split out an additional reg-reg
;; copy or constant load before the actual add insn.
;; Use u constraint for that case to avoid the invalid value in the stack
;; pointer.
;; This also results in better code when LRA is not used.  However, we have
;; to use different sets of patterns and the order of these patterns is
;; important.
;; In some cases the constant zero might end up in operands[2] of the
;; patterns.  We have to accept that and convert it into a reg-reg move.
(define_insn_and_split "*addsi3_compact_lra"
  [(set (match_operand:SI 0 "arith_reg_dest" "=r,&u")
        (plus:SI (match_operand:SI 1 "arith_reg_operand" "%0,r")
                 (match_operand:SI 2 "arith_or_int_operand" "rI08,rn")))]
  "TARGET_SH1 && sh_lra_p ()
   && (! reg_overlap_mentioned_p (operands[0], operands[1])
       || arith_operand (operands[2], SImode))"
  "@
        add     %2,%0
        #"
  "&& reload_completed
   && ! reg_overlap_mentioned_p (operands[0], operands[1])"
  [(set (match_dup 0) (match_dup 2))
   (set (match_dup 0) (plus:SI (match_dup 0) (match_dup 1)))]
{
  /* Prefer 'mov r0,r1; add #imm8,r1' over 'mov #imm8,r1; add r0,r1'  */
  if (satisfies_constraint_I08 (operands[2]))
    std::swap (operands[1], operands[2]);
}
  [(set_attr "type" "arith")])

[Bug target/100782] [11 Regression] sh4 ICEs on -O2 -fPIE -fstack-protector: internal compiler error: in curr_insn_transform, at lra-constraints.c:4132

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100782

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|11.3                        |11.4

--- Comment #7 from Richard Biener <rguenth at gcc dot gnu.org> ---
GCC 11.3 is being released, retargeting bugs to GCC 11.4.

[Bug target/100782] [11 Regression] sh4 ICEs on -O2 -fPIE -fstack-protector: internal compiler error: in curr_insn_transform, at lra-constraints.c

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100782

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|11.4                        |11.5

--- Comment #8 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
GCC 11.4 is being released, retargeting bugs to GCC 11.5.