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cse.c (flush_hash_table): New function.

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* cse.c (flush_hash_table): New function.
        (cse_insn): Flush the hash table when we encounter a volatile asm.
        (cse_basic_block): Use flush_hash_table instead of doing it
        inline.
        * reload1.c (reload_cse_regs_1): Flush known register values if
        we encounter a volatile asm.

From-SVN: r26304
This commit is contained in:
Jeffrey A Law 1999-04-09 00:29:45 +00:00 committed by Jeff Law
parent 3fb2a045ec
commit 01e752d386
3 changed files with 46 additions and 13 deletions
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8
gcc/ChangeLog
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@ -1,5 +1,13 @@
Thu Apr 8 19:20:18 1999 Jeffrey A Law (law@cygnus.com)
* cse.c (flush_hash_table): New function.
(cse_insn): Flush the hash table when we encounter a volatile asm.
(cse_basic_block): Use flush_hash_table instead of doing it
inline.
* reload1.c (reload_cse_regs_1): Flush known register values if
we encounter a volatile asm.
* loop.c (strength_reduce): Re-enable Joern's loop improvements.
Thu Apr 8 09:37:40 1999 Nick Clifton <nickc@cygnus.com>

43
gcc/cse.c
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@ -691,6 +691,7 @@ extern void dump_class PROTO((struct table_elt*));
static void check_fold_consts PROTO((PTR));
static struct cse_reg_info* get_cse_reg_info PROTO((int));
static void free_cse_reg_info PROTO((splay_tree_value));
static void flush_hash_table PROTO((void));
extern int rtx_equal_function_value_matters;
@ -1666,6 +1667,28 @@ merge_equiv_classes (class1, class2)
}
}
/* Flush the entire hash table. */
static void
flush_hash_table ()
{
int i;
struct table_elt *p;
for (i = 0; i < NBUCKETS; i++)
for (p = table[i]; p; p = table[i])
{
/* Note that invalidate can remove elements
after P in the current hash chain. */
if (GET_CODE (p->exp) == REG)
invalidate (p->exp, p->mode);
else
remove_from_table (p, i);
}
}
/* Remove from the hash table, or mark as invalid,
all expressions whose values could be altered by storing in X.
X is a register, a subreg, or a memory reference with nonvarying address
@ -7648,6 +7671,12 @@ cse_insn (insn, libcall_insn)
invalidate (XEXP (dest, 0), GET_MODE (dest));
}
/* A volatile ASM invalidates everything. */
if (GET_CODE (insn) == INSN
&& GET_CODE (PATTERN (insn)) == ASM_OPERANDS
&& MEM_VOLATILE_P (PATTERN (insn)))
flush_hash_table ();
/* Make sure registers mentioned in destinations
are safe for use in an expression to be inserted.
This removes from the hash table
@ -8855,8 +8884,6 @@ cse_basic_block (from, to, next_branch, around_loop)
for (insn = from; insn != to; insn = NEXT_INSN (insn))
{
register enum rtx_code code = GET_CODE (insn);
int i;
struct table_elt *p;
/* If we have processed 1,000 insns, flush the hash table to
avoid extreme quadratic behavior. We must not include NOTEs
@ -8869,17 +8896,7 @@ cse_basic_block (from, to, next_branch, around_loop)
Perhaps for 2.9. */
if (code != NOTE && num_insns++ > 1000)
{
for (i = 0; i < NBUCKETS; i++)
for (p = table[i]; p; p = table[i])
{
/* Note that invalidate can remove elements
after P in the current hash chain. */
if (GET_CODE (p->exp) == REG)
invalidate (p->exp, p->mode);
else
remove_from_table (p, i);
}
flush_hash_table ();
num_insns = 0;
}

8
gcc/reload1.c
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@ -8740,6 +8740,14 @@ reload_cse_regs_1 (first)
reload_cse_invalidate_mem (callmem);
}
/* Forget all the register values at a volatile asm. */
if (GET_CODE (insn) == INSN
&& GET_CODE (PATTERN (insn)) == ASM_OPERANDS
&& MEM_VOLATILE_P (PATTERN (insn)))
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
reg_values[i] = 0;
body = PATTERN (insn);
if (GET_CODE (body) == SET)
{