> The PIC register setup code is emitted after NOTE_INSNS_FUNCTION_BEG,
> because it uses the insert_insn_on_edge mechanism, and the corresponding
> insertion in cfgexpand.c:gimple_expand_cfg takes care to insert the code
> after the parm_birth_insn:
> ...
> /* Avoid putting insns before parm_birth_insn. */
> if (e->src == ENTRY_BLOCK_PTR
> && single_succ_p (ENTRY_BLOCK_PTR)
> && parm_birth_insn)
> {
> rtx insns = e->insns.r;
> e->insns.r = NULL_RTX;
> emit_insn_after_noloc (insns, parm_birth_insn, e->dest);
> }
> ...
> And in the case for this test-case, parm_birth_insn is the
> NOTE_INSNS_FUNCTION_BEG.
So this means that parm_birth_insn can never be null, right?
> 2013-10-13 Tom de Vries <t...@codesourcery.com>
>
> * cfgexpand.c (gimple_expand_cfg): Don't commit insertions after
> NOTE_INSN_FUNCTION_BEG.
>
> * gcc.target/arm/require-pic-register-loc.c: New test.
OK if you also remove the test on parm_birth_insn.
--
Eric Botcazou
