On Fri, Feb 14, 2014 at 4:19 PM, Kai Tietz <ktiet...@googlemail.com> wrote:
> Adjusted my original testcase so that eax isn't redeclared and
> shadows. Additional moved
> initialization of eax_live up.
> ChangeLog
>
> 2014-02-14 Kai Tietz <kti...@redhat.com>
>
> PR target/60193
> * config/i386/i386.c (ix86_expand_prologue): Use
> rax register as displacement for restoring %r10, %rax.
> Additional fix wrong offset for restoring both-registers.
>
> ChangeLog testsuite
>
> 2014-02-14 Kai Tietz <kti...@redhat.com>
>
> PR target/60193
> * gcc.target/i386/nest-1.c: New testcase.
>
> Regression-tested for x86_64-unknown-linux-gnu, and
> x86_64-w64-mingw32, and i686-w64-mingw32. Ok for apply?
>
> Regards,
> Kai
>
> Index: i386.c
> ===================================================================
> --- i386.c (Revision 207686)
> +++ i386.c (Arbeitskopie)
> @@ -11023,13 +11023,12 @@ ix86_expand_prologue (void)
> rtx r10 = NULL;
> rtx (*adjust_stack_insn)(rtx, rtx, rtx);
> const bool sp_is_cfa_reg = (m->fs.cfa_reg == stack_pointer_rtx);
> - bool eax_live = false;
> + bool eax_live = ix86_eax_live_at_start_p ();
> bool r10_live = false;
>
> if (TARGET_64BIT)
> r10_live = (DECL_STATIC_CHAIN (current_function_decl) != 0);
>
> - eax_live = ix86_eax_live_at_start_p ();
> if (eax_live)
> {
> insn = emit_insn (gen_push (eax));
> @@ -11084,17 +11083,20 @@ ix86_expand_prologue (void)
> works for realigned stack, too. */
> if (r10_live && eax_live)
> {
> - t = plus_constant (Pmode, stack_pointer_rtx, allocate);
> + t = gen_rtx_PLUS (Pmode, stack_pointer_rtx, eax);
> emit_move_insn (gen_rtx_REG (word_mode, R10_REG),
> gen_frame_mem (word_mode, t));
> - t = plus_constant (Pmode, stack_pointer_rtx,
> - allocate - UNITS_PER_WORD);
> +
> + t = plus_constant (Pmode, eax, UNITS_PER_WORD);
> + emit_move_insn (eax, t);
> + t = gen_rtx_PLUS (Pmode, stack_pointer_rtx, eax);
only
t = plus_constant (Pmode, t, UNITS_PER_WORD);
is enough here.
> emit_move_insn (gen_rtx_REG (word_mode, AX_REG),
> gen_frame_mem (word_mode, t));
> }
> else if (eax_live || r10_live)
> {
> - t = plus_constant (Pmode, stack_pointer_rtx, allocate);
> + /* Don't exceed displacement-range for 64-bit. */
Stalled comment.
