On 12/10/20 4:20 AM, Maciej W. Rozycki wrote:
> Fix an issue with the `casesi' expander using `GEN_INT' to produce the
> constant rtx for lower bound adjustment. This generates a VOIDmode
> value which may overflow the SImode range required for the operand to
> stay within to satisfy `general_operand', resulting in an ICE like:
>
> .../gcc/testsuite/gcc.c-torture/compile/pr46934.c: In function 'caller':
> .../gcc/testsuite/gcc.c-torture/compile/pr46934.c:17:1: error: unrecognizable
> insn:
> (insn 5 2 6 2 (set (reg:SI 25)
> (plus:SI (mem/c:SI (reg/f:SI 17 virtual-incoming-args) [1 reg_type+0
> S4 A32])
> (const_int 2147483648 [0x80000000]))) -1
> (nil))
> during RTL pass: vregs
> .../gcc/testsuite/gcc.c-torture/compile/pr46934.c:17:1: internal compiler
> error: in extract_insn, at recog.c:2315
> 0x110d4673 _fatal_insn(char const*, rtx_def const*, char const*, int, char
> const*)
> .../gcc/rtl-error.c:108
> 0x110d46eb _fatal_insn_not_found(rtx_def const*, char const*, int, char
> const*)
> .../gcc/rtl-error.c:116
> 0x1106578b extract_insn(rtx_insn*)
> .../gcc/recog.c:2315
> 0x10b63f73 instantiate_virtual_regs_in_insn
> .../gcc/function.c:1609
> 0x10b65b2f instantiate_virtual_regs
> .../gcc/function.c:1979
> 0x10b65ca7 execute
> .../gcc/function.c:2028
> 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.
> compiler exited with status 1
> FAIL: gcc.c-torture/compile/pr46934.c -O0 (internal compiler error)
>
> Use `gen_int_mode' to produce the rtx instead, requesting a SImode value
> so that the constant gets correctly truncated:
>
> @@ -199,7 +199,7 @@ caller (unsigned int reg_type)
>
> (insn 5 4 6 (set (reg:SI 25)
> (plus:SI (mem/c:SI (reg/f:SI 17 virtual-incoming-args) [1 reg_type+0
> S4 A32])
> - (const_int 2147483648 [0x80000000]))) -1
> + (const_int -2147483648 [0xffffffff80000000]))) -1
> (nil))
>
> (jump_insn 6 5 7 (set (pc)
>
> removing these test suite failures:
>
> FAIL: gcc.c-torture/compile/pr46934.c -O0 (internal compiler error)
> FAIL: gcc.c-torture/compile/pr46934.c -O0 (test for excess errors)
>
> with the `vax-netbsdelf' target.
>
> gcc/
> * config/vax/vax.md (casesi): Use `gen_int_mode' rather than
> `GEN_INT' for the immediate used for lower bound adjustment.
OK
jeff
