On Mon, Nov 12, 2012 at 9:40 AM, Eric Botcazou <ebotca...@adacore.com> wrote: >> It looks to me, that we in fact want: >> >> --cut here-- >> Index: mode-switching.c >> =================================================================== >> --- mode-switching.c (revision 193407) >> +++ mode-switching.c (working copy) >> @@ -330,7 +330,7 @@ >> short_block = 1; >> break; >> } >> - if (copy_start >= FIRST_PSEUDO_REGISTER) >> + if (!targetm.calls.function_value_regno_p (copy_start)) >> { >> last_insn = return_copy; >> continue; >> --cut here-- >> >> If we find an unrelated HARD register, we will fail in the same way as >> described in the PR. This was found by post-reload vzeroupper >> insertion pass that tripped on unrelated hard reg assignment. At this >> point, we are interested only in hard registers that are also used for >> function return value. Actually, even in pre-reload pass, there are no >> other assignments to hard registers. > > Fine with me if this passes testing on x86-avx and SH4.
Committed to mailine SVN with additional restriction, we only want to scan instructions that are not debug instructions. 2012-11-13 Uros Bizjak <ubiz...@gmail.com> PR target/41993 * mode-switching.c (create_pre_exit): Set return_copy to last_insn if copy_start is not a function return regno. Skip debug instructions in instruction scan loop. Bootstrapped and regression tested on SH4 by Kaz and Oleg, on AVX target by Vladimir and by me on x86_64-pc-linux-gnu {,-m32 -} AVX target, configured with "--with-arch=corei7-avx --with-cpu=corei7-avx --enable-languages=all,obj-c++,go" with and without postreload vzeroupper insertion patch. Uros.
Index: mode-switching.c =================================================================== --- mode-switching.c (revision 193479) +++ mode-switching.c (working copy) @@ -242,7 +242,8 @@ create_pre_exit (int n_entities, int *entity_map, int copy_start, copy_num; int j; - if (INSN_P (return_copy)) + if (INSN_P (return_copy) + && !DEBUG_INSN_P (return_copy)) { /* When using SJLJ exceptions, the call to the unregister function is inserted between the @@ -330,7 +331,7 @@ create_pre_exit (int n_entities, int *entity_map, short_block = 1; break; } - if (copy_start >= FIRST_PSEUDO_REGISTER) + if (!targetm.calls.function_value_regno_p (copy_start)) { last_insn = return_copy; continue;