@@ -6190,8 +6190,15 @@ ix86_init_pic_reg (void)
}
else
{
- rtx insn = emit_insn (gen_set_got (pic_offset_table_rtx));
+ /* If there is future mcount call in the function it is more profitable
+ to emit SET_GOT into ABI defined REAL_PIC_OFFSET_TABLE_REGNUM. */
+ rtx reg = crtl->profile
+ ? gen_rtx_REG (Pmode, REAL_PIC_OFFSET_TABLE_REGNUM)
+ : pic_offset_table_rtx;
+ rtx insn = emit_insn (gen_set_got (reg));
RTX_FRAME_RELATED_P (insn) = 1;
+ if (crtl->profile)
+ emit_move_insn (pic_offset_table_rtx, reg);
add_reg_note (insn, REG_CFA_FLUSH_QUEUE, NULL_RTX);
}
@@ -9471,15 +9478,23 @@ ix86_select_alt_pic_regnum (void)
static bool
ix86_save_reg (unsigned int regno, bool maybe_eh_return)
{
- if (pic_offset_table_rtx
- && !ix86_use_pseudo_pic_reg ()
- && regno == REAL_PIC_OFFSET_TABLE_REGNUM
- && (df_regs_ever_live_p (REAL_PIC_OFFSET_TABLE_REGNUM)
- || crtl->profile
- || crtl->calls_eh_return
- || crtl->uses_const_pool
- || cfun->has_nonlocal_label))
- return ix86_select_alt_pic_regnum () == INVALID_REGNUM;
+ if (regno == REAL_PIC_OFFSET_TABLE_REGNUM
+ && pic_offset_table_rtx)
+ {
+ if (ix86_use_pseudo_pic_reg ())
+ {
+ /* REAL_PIC_OFFSET_TABLE_REGNUM used by call to
+ _mcount in prologue. */
+ if (!TARGET_64BIT && flag_pic && crtl->profile)
+ return true;
+ }
+ else if (df_regs_ever_live_p (REAL_PIC_OFFSET_TABLE_REGNUM)
+ || crtl->profile
+ || crtl->calls_eh_return
+ || crtl->uses_const_pool
+ || cfun->has_nonlocal_label)
+ return ix86_select_alt_pic_regnum () == INVALID_REGNUM;
+ }
if (crtl->calls_eh_return && maybe_eh_return)
{
@@ -10818,6 +10833,29 @@ ix86_finalize_stack_realign_flags (void)
crtl->stack_realign_finalized = true;
}
+/* Delete SET_GOT right after entry block if it is allocated to reg. */
+
+static void
+ix86_elim_entry_set_got (rtx reg)
+{
+ basic_block bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb;
+ rtx_insn *c_insn = BB_HEAD (bb);
+ if (!NONDEBUG_INSN_P (c_insn))
+ c_insn = next_nonnote_nondebug_insn (c_insn);
+ if (c_insn && NONJUMP_INSN_P (c_insn))
+ {
+ rtx pat = PATTERN (c_insn);
+ if (GET_CODE (pat) == PARALLEL)
+ {
+ rtx vec = XVECEXP (pat, 0, 0);
+ if (GET_CODE (vec) == SET
+ && XINT (XEXP (vec, 1), 1) == UNSPEC_SET_GOT
+ && REGNO (XEXP (vec, 0)) == REGNO (reg))
+ delete_insn (c_insn);
+ }
+ }
+}
+
/* Expand the prologue into a bunch of separate insns. */
void
@@ -11271,6 +11309,20 @@ ix86_expand_prologue (void)
if (!sse_registers_saved)
ix86_emit_save_sse_regs_using_mov (frame.sse_reg_save_offset);
+ /* For the mcount profiling on 32 bit PIC mode we need to emit SET_GOT
+ in PROLOGUE. */
+ if (!TARGET_64BIT && pic_offset_table_rtx && crtl->profile && !flag_fentry)
+ {
+ rtx pic = gen_rtx_REG (Pmode, REAL_PIC_OFFSET_TABLE_REGNUM);
+ insn = emit_insn (gen_set_got (pic));
+ RTX_FRAME_RELATED_P (insn) = 1;
+ add_reg_note (insn, REG_CFA_FLUSH_QUEUE, NULL_RTX);
+ emit_insn (gen_prologue_use (pic));
+ /* Deleting already emmitted SET_GOT if exist and allocated to
+ REAL_PIC_OFFSET_TABLE_REGNUM. */
+ ix86_elim_entry_set_got (pic);
+ }
+
if (crtl->drap_reg && !crtl->stack_realign_needed)
{
/* vDRAP is setup but after reload it turns out stack realign
b/gcc/testsuite/gcc.target/i386/mcount_pic.c
new file mode 100644
@@ -0,0 +1,15 @@
+/* PR target/63534 */
+/* Check correct mcount generation. */
+/* { dg-do run } */
+/* { dg-require-effective-target fpic } */
+/* { dg-require-effective-target ia32 } */
+/* { dg-options "-O2 -fpic -p -save-temps" } */
+
+int main ()
+{
+ return 0;
+}
+
+/* { dg-final { scan-assembler "mcount" } } */
+/* { dg-final { scan-assembler "get_pc_thunk" } } */
+/* { dg-final { cleanup-saved-temps } } */
Patch with the fixes: Bootstrap, gcc make check and spec2000 with "-p" passed. 2014-10-29 Evgeny Stupachenko <evstupac@gmail.com> gcc/testsuite PR target/63534 * gcc.target/i386/mcount_pic.c: New. gcc/ PR target/63534 * config/i386/i386.c (ix86_init_pic_reg): Emit SET_GOT to REAL_PIC_OFFSET_TABLE_REGNUM for mcount profiling. (ix86_save_reg): Save REAL_PIC_OFFSET_TABLE_REGNUM when profiling using mcount in 32bit PIC mode. (ix86_elim_entry_set_got): New. (ix86_expand_prologue): For the mcount profiling emit new SET_GOT in PROLOGUE, delete initial if possible. On Tue, Oct 28, 2014 at 9:19 PM, Jakub Jelinek <jakub@redhat.com> wrote: > On Tue, Oct 28, 2014 at 06:28:29PM +0300, Evgeny Stupachenko wrote: > >> +/* Delete SET_GOT right after entry block if it is allocated to reg. */ >> + >> +static void >> +ix86_elim_entry_set_got (rtx reg) >> +{ >> + basic_block bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb; >> + rtx_insn *c_insn; >> + FOR_BB_INSNS (bb, c_insn) >> + if (GET_CODE (c_insn) != NOTE) >> + break; > > This might result in -fcompare-debug failure, if there is > a DEBUG_INSN before the UNSPEC_SET_GOT. Also, if the first bb > contains only NOTE insns, you'd crash. > I'd use instead: > rtx_insn *c_insn = BB_HEAD (bb); > if (!NONDEBUG_INSN_P (c_insn)) > c_insn = next_nonnote_nondebug_insn (c_insn); > if (c_insn && NONJUMP_INSN_P (c_insn)) > or so. > >> + if (NONJUMP_INSN_P (c_insn)) > >> --- /dev/null >> +++ b/gcc/testsuite/gcc.target/i386/mcount_pic.c >> @@ -0,0 +1,13 @@ >> +/* Test check correct mcount generation. */ >> +/* { dg-do run } */ >> +/* { dg-require-effective-target ia32 } */ >> +/* { dg-options "-O2 -fpic -p -save-temps" } */ > > Please put the PR also in the testcase comment. > And, -fpic needs to be guarded by { target fpic }, though > as get_pc_thunk will not appear in non-pic code, I think > you want /* { dg-do run { target fpic } } */. > > Otherwise LGTM. > > Jakub