[Bug rtl-optimization/105231] [12 Regression] ICE: in rtl_verify_bb_insns, at cfgrtl.cc:2797 (flow control insn inside a basic block) with custom flags since r12-4767-g81342e95827f77c0

[ebotcazou at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105231

--- Comment #6 from Eric Botcazou <ebotcazou at gcc dot gnu.org> ---
> So interestingly distribute_notes sees
> 
> (gdb) p debug_rtx (i2)
> (insn 78 22 24 3 (set (reg:XF 99)
>         (float_extend:XF (mem/u/c:SF (symbol_ref/u:SI ("*.LC0") [flags 0x2])
> [0  S4 A32]))) 166 {*extendsfxf2_i387}
>      (nil))
> 
> as may_trap_p (), but we did not place an EH note on this previously.  I'm
> not sure how the RTL IL is sanitized but eventually we simply take what RTL
> expansion yields as granted.

This is the insn before combine though:

(insn 78 22 24 3 (set (reg:XF 99)
        (float_extend:XF (reg:SF 92))) 166 {*extendsfxf2_i387}
     (expr_list:REG_DEAD (reg:SF 92)
        (expr_list:REG_EQUAL (const_double:XF 1.8446744073709551616e+19
[0x0.8p+65])
            (nil))))

so combine apparently forced the constant into the constant pool.