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riscv-gcc-1
Commit 89098dc1 by Jeff Law
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regmove.c (optimize_reg_copy_1): Undo Aug 18 change. 

        * regmove.c (optimize_reg_copy_1): Undo Aug 18 change.  Update
        REG_N_CALLS_CROSSED and REG_LIVE_LENGH if and only if we change
        where a register is live.

From-SVN: r24718
parent 20f7cbac
Showing with 38 additions and 49 deletions
gcc/ChangeLog
Sun Jan 17 19:23:20 1999 Jeffrey A Law (law@cygnus.com)
* regmove.c (optimize_reg_copy_1): Undo Aug 18 change. Update
REG_N_CALLS_CROSSED and REG_LIVE_LENGH if and only if we change
where a register is live.
Sun Jan 17 03:20:47 1999 H.J. Lu (hjl@gnu.org)
* reg-stack.c (subst_stack_regs_pat): Abort if the destination
of a FP conditional move is not on the FP register stack.
Sun Jan 17 01:15:04 PST 1999 Jeff Law (law@cygnus.com)
* version.c: Bump for snapshot.
......
gcc/regmove.c
......@@ -253,10 +253,10 @@ optimize_reg_copy_1 (insn, dest, src)
&& GET_MODE (XEXP (note, 0)) == GET_MODE (src))
{
int failed = 0;
int length = 0;
int d_length = 0;
int n_calls = 0;
int s_length = 0;
int d_n_calls = 0;
int s_n_calls = 0;
/* We can do the optimization. Scan forward from INSN again,
replacing regs as we go. Set FAILED if a replacement can't
......@@ -290,42 +290,14 @@ optimize_reg_copy_1 (insn, dest, src)
insn in the REG_N_REFS updates below. If this is not
correct, no great harm is done.
We do not undo this substitution if something later
fails. Therefore, we must update the other REG_N_*
counters now to keep them accurate. */
Since we do not know if we will change the lifetime of
SREGNO or DREGNO, we must not update REG_LIVE_LENGTH
or REG_N_CALLS_CROSSED at this time. */
if (sregno >= FIRST_PSEUDO_REGISTER)
{
REG_N_REFS (sregno) -= loop_depth;
if (REG_LIVE_LENGTH (sregno) >= 0)
{
REG_LIVE_LENGTH (sregno) -= length;
/* REG_LIVE_LENGTH is only an approximation after
combine if sched is not run, so make sure that
we still have a reasonable value. */
if (REG_LIVE_LENGTH (sregno) < 2)
REG_LIVE_LENGTH (sregno) = 2;
}
REG_N_CALLS_CROSSED (sregno) -= n_calls;
}
REG_N_REFS (sregno) -= loop_depth;
if (dregno >= FIRST_PSEUDO_REGISTER)
{
REG_N_REFS (dregno) += loop_depth;
if (REG_LIVE_LENGTH (dregno) >= 0)
REG_LIVE_LENGTH (dregno) += d_length;
REG_N_CALLS_CROSSED (dregno) += d_n_calls;
}
/* We've done a substitution, clear the counters. */
length = 0;
d_length = 0;
n_calls = 0;
d_n_calls = 0;
REG_N_REFS (dregno) += loop_depth;
}
else
{
......@@ -334,9 +306,10 @@ optimize_reg_copy_1 (insn, dest, src)
}
}
/* Count the insns and CALL_INSNs passed. If we passed the
death note of DEST, show increased live length. */
length++;
/* For SREGNO, count the total number of insns scanned.
For DREGNO, count the total number of insns scanned after
passing the death note for DREGNO. */
s_length++;
if (dest_death)
d_length++;
......@@ -344,7 +317,9 @@ optimize_reg_copy_1 (insn, dest, src)
as a call that has been crossed. Otherwise, count it. */
if (q != p && GET_CODE (q) == CALL_INSN)
{
n_calls++;
/* Similarly, total calls for SREGNO, total calls beyond
the death note for DREGNO. */
s_n_calls++;
if (dest_death)
d_n_calls++;
}
......@@ -364,11 +339,13 @@ optimize_reg_copy_1 (insn, dest, src)
if (! failed)
{
/* These counters need to be updated if and only if we are
going to move the REG_DEAD note. */
if (sregno >= FIRST_PSEUDO_REGISTER)
{
if (REG_LIVE_LENGTH (sregno) >= 0)
{
REG_LIVE_LENGTH (sregno) -= length;
REG_LIVE_LENGTH (sregno) -= s_length;
/* REG_LIVE_LENGTH is only an approximation after
combine if sched is not run, so make sure that we
still have a reasonable value. */
......@@ -376,15 +353,7 @@ optimize_reg_copy_1 (insn, dest, src)
REG_LIVE_LENGTH (sregno) = 2;
}
REG_N_CALLS_CROSSED (sregno) -= n_calls;
}
if (dregno >= FIRST_PSEUDO_REGISTER)
{
if (REG_LIVE_LENGTH (dregno) >= 0)
REG_LIVE_LENGTH (dregno) += d_length;
REG_N_CALLS_CROSSED (dregno) += d_n_calls;
REG_N_CALLS_CROSSED (sregno) -= s_n_calls;
}
/* Move death note of SRC from P to INSN. */
......@@ -398,6 +367,15 @@ optimize_reg_copy_1 (insn, dest, src)
{
XEXP (dest_death, 1) = REG_NOTES (p);
REG_NOTES (p) = dest_death;
if (dregno >= FIRST_PSEUDO_REGISTER)
{
/* If and only if we are moving the death note for DREGNO,
then we need to update its counters. */
if (REG_LIVE_LENGTH (dregno) >= 0)
REG_LIVE_LENGTH (dregno) += d_length;
REG_N_CALLS_CROSSED (dregno) += d_n_calls;
}
}
return ! failed;
......
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