@@ -14659,20 +14659,20 @@ mips_orphaned_high_part_p (htab_t htab,
INSN and a previous instruction, avoid it by inserting nops after
instruction AFTER.
- *DELAYED_REG and *HILO_DELAY describe the hazards that apply at
- this point. If *DELAYED_REG is non-null, INSN must wait a cycle
- before using the value of that register. *HILO_DELAY counts the
- number of instructions since the last hilo hazard (that is,
- the number of instructions since the last MFLO or MFHI).
+ *DELAYED_REG, *SET_AFTER and *HILO_DELAY describe the hazards that
+ apply at this point. If *DELAYED_REG and *SET_AFTER is non-null,
+ INSN must wait a cycle before using the value of that register.
+ *HILO_DELAY counts the number of instructions since the last hilo hazard
+ (that is, the number of instructions since the last MFLO or MFHI).
- After inserting nops for INSN, update *DELAYED_REG and *HILO_DELAY
- for the next instruction.
+ After inserting nops for INSN, update *DELAYED_REG, *SET_AFTER
+ and *HILO_DELAY for the next instruction.
LO_REG is an rtx for the LO register, used in dependence checking. */
static void
mips_avoid_hazard (rtx after, rtx insn, int *hilo_delay,
- rtx *delayed_reg, rtx lo_reg)
+ rtx *delayed_reg, rtx lo_reg, rtx *set_after)
{
rtx pattern, set;
int nops, ninsns;
@@ -14696,7 +14696,9 @@ mips_avoid_hazard (rtx after, rtx insn,
clobber hi and lo. */
if (*hilo_delay < 2 && reg_set_p (lo_reg, pattern))
nops = 2 - *hilo_delay;
- else if (*delayed_reg != 0 && reg_referenced_p (*delayed_reg, pattern))
+ else if ((*delayed_reg != 0 && set_after != 0 && reg_referenced_p (*delayed_reg, pattern))
+ && !(recog_memoized (insn) == CODE_FOR_load_highdf
+ && recog_memoized (*set_after) == CODE_FOR_load_lowdf))
nops = 1;
else
nops = 0;
@@ -14710,6 +14712,7 @@ mips_avoid_hazard (rtx after, rtx insn,
/* Set up the state for the next instruction. */
*hilo_delay += ninsns;
*delayed_reg = 0;
+ *set_after = 0;
if (INSN_CODE (insn) >= 0)
switch (get_attr_hazard (insn))
{
@@ -14724,6 +14727,7 @@ mips_avoid_hazard (rtx after, rtx insn,
set = single_set (insn);
gcc_assert (set);
*delayed_reg = SET_DEST (set);
+ *set_after = insn;
break;
}
}
@@ -14736,7 +14740,7 @@ mips_avoid_hazard (rtx after, rtx insn,
static void
mips_reorg_process_insns (void)
{
- rtx insn, last_insn, subinsn, next_insn, lo_reg, delayed_reg;
+ rtx insn, last_insn, subinsn, next_insn, lo_reg, delayed_reg, set_after;
int hilo_delay;
htab_t htab;
@@ -14811,7 +14815,7 @@ mips_reorg_process_insns (void)
INSN_CODE (subinsn) = CODE_FOR_nop;
}
mips_avoid_hazard (last_insn, subinsn, &hilo_delay,
- &delayed_reg, lo_reg);
+ &delayed_reg, lo_reg, &set_after);
}
last_insn = insn;
}
@@ -14832,7 +14836,7 @@ mips_reorg_process_insns (void)
else
{
mips_avoid_hazard (last_insn, insn, &hilo_delay,
- &delayed_reg, lo_reg);
+ &delayed_reg, lo_reg, &set_after);
last_insn = insn;
}
}
hi, Richard, This version of patch showed no regressions on mipsel-unknown-linux-gnu. Thanks, Dinar. On Wed, Sep 21, 2011 at 4:59 PM, Richard Sandiford <rdsandiford@googlemail.com> wrote: > Dinar Temirbulatov <dtemirbulatov@gmail.com> writes: >> @@ -14696,7 +14696,11 @@ mips_avoid_hazard (rtx after, rtx insn, >> clobber hi and lo. */ >> if (*hilo_delay < 2 && reg_set_p (lo_reg, pattern)) >> nops = 2 - *hilo_delay; >> - else if (*delayed_reg != 0 && reg_referenced_p (*delayed_reg, pattern)) >> + else if ((*delayed_reg != 0 && reg_referenced_p (*delayed_reg, pattern)) >> + && !((GET_MODE (*delayed_reg) == DFmode && set_after != 0 >> + && (set = single_set (insn)) != NULL_RTX && GET_MODE (SET_DEST(set)) == DFmode >> + && XINT((XEXP (pattern, 1)), 1) == UNSPEC_LOAD_HIGH >> + && XINT((XEXP (*set_after, 1)), 1) == UNSPEC_LOAD_LOW))) > > This isn't safe because the patterns might not be UNSPECs (so XINT (...) > would be meaningless). It's better to check the insn code instead. > Something like: > > else if (*delayed_reg != 0 > && reg_referenced_p (*delayed_reg, pattern) > && !(recog_memoized (insn) == CODE_FOR_load_highdf > && recog_memoized (*set_after) == CODE_FOR_load_lowdf)) > > (untested). Note that *set_after should always be nonnull if > *delayed_reg is. > > Looks good otherwise. > > Richard >