OpenE2K
/
gcc
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

(combine_instructions): When calling set_nonzero_bits_and_sign_copies, 

set things up so that we can call get_last value; call
record_dead_and_set_regs in loop.
(set_nonzero_bits_and_sign_copies): Handle paradoxical SET.

From-SVN: r3444
This commit is contained in:
Richard Kenner 1993-02-09 05:45:36 -05:00
parent b6542989bc
commit d79f08e0b8
1 changed files with 31 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

34
gcc/combine.c
View File

@ -451,13 +451,27 @@ combine_instructions (f, nregs)
Scan all SETs and see if we can deduce anything about what
bits are known to be zero for some registers and how many copies
of the sign bit are known to exist for those registers. */
of the sign bit are known to exist for those registers.
Also set any known values so that we can use it while searching
for what bits are known to be set. */
label_tick = 1;
for (insn = f, i = 0; insn; insn = NEXT_INSN (insn))
{
INSN_CUID (insn) = ++i;
subst_low_cuid = i;
subst_insn = insn;
if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
note_stores (PATTERN (insn), set_nonzero_bits_and_sign_copies);
{
note_stores (PATTERN (insn), set_nonzero_bits_and_sign_copies);
record_dead_and_set_regs (insn);
}
if (GET_CODE (insn) == CODE_LABEL)
label_tick++;
}
nonzero_sign_valid = 1;
@ -467,6 +481,12 @@ combine_instructions (f, nregs)
label_tick = 1;
last_call_cuid = 0;
mem_last_set = 0;
bzero (reg_last_death, nregs * sizeof (rtx));
bzero (reg_last_set, nregs * sizeof (rtx));
bzero (reg_last_set_value, nregs * sizeof (rtx));
bzero (reg_last_set_table_tick, nregs * sizeof (short));
bzero (reg_last_set_label, nregs * sizeof (short));
bzero (reg_last_set_invalid, nregs * sizeof (char));
for (insn = f; insn; insn = next ? next : NEXT_INSN (insn))
{
@ -606,7 +626,15 @@ set_nonzero_bits_and_sign_copies (x, set)
/* If this is a complex assignment, see if we can convert it into a
simple assignment. */
set = expand_field_assignment (set);
if (SET_DEST (set) == x)
/* If this is a simple assignment, or we have a paradoxical SUBREG,
set what we know about X. */
if (SET_DEST (set) == x
|| (GET_CODE (SET_DEST (set)) == SUBREG
&& (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
> GET_MODE_SIZE (GET_MODE (SUBREG_REG (SET_DEST (x)))))
&& SUBREG_REG (SET_DEST (set)) == x))
{
reg_nonzero_bits[REGNO (x)]
|= nonzero_bits (SET_SRC (set), nonzero_bits_mode);