Hello Vlad,
Is it intentional that DF_LR_IN and DF_LR_OUT are not updated after
"Updating elimination of equiv for reg..."? I have some checking in
place in process_bb_lives at the end of the function, and it triggers
on the test case. (Checking code and test case is at the end of this
e-mail.) It show:
LIVEIN-mismatch in bb 5:
66, 69,
66, 69, 73
73
t.c: In function 'get_mem_attrs':
t.c:47:1: internal compiler error: in process_bb_lives, at lra-lives.c:866
}
^
And that's correct if you look at the LR_IN set of basic block 5 in
the IRA (.193r.ira) dump:
;; basic block 2, loop depth 0, count 0, freq 10000, maybe hot
...
9 r73:SI=[argp:DI]
REG_EQUIV: [argp:DI]
...
;; lr out 6 [bp] 7 [sp] 16 [argp] 20 [frame] 66 69 73
...
;; basic block 5, loop depth 0, count 0, freq 5014, maybe hot
;; prev block 4, next block 6, flags: (RTL)
;; pred: 4
;; bb 5 artificial_defs: { }
;; bb 5 artificial_uses: { u22(6){ }u23(7){ }u24(16){ }u25(20){ }}
;; lr in 6 [bp] 7 [sp] 16 [argp] 20 [frame] 66 69 73
;; lr use 6 [bp] 7 [sp] 16 [argp] 20 [frame] 69 73
;; lr def 17 [flags] 74 76
;; live in 6 [bp] 7 [sp] 16 [argp] 20 [frame] 66 69 73
;; live gen 17 [flags] 74 76
;; live kill
23 NOTE_INSN_BASIC_BLOCK
24 r74:DI=sign_extend(r73:SI)
REG_DEAD: r73:SI
26 r76:DI=zero_extend([r74:DI+`mode_size'])
REG_DEAD: r74:DI
27 flags:CCZ=cmp(r76:DI,[r69:DI])
REG_DEAD: r76:DI
REG_DEAD: r69:DI
28 pc={(flags:CCZ==0)?L57:pc}
REG_DEAD: flags:CCZ
REG_BR_PROB: 0x19e
;; succ: 8
;; 6
;; lr out 6 [bp] 7 [sp] 16 [argp] 20 [frame] 66
;; live out 6 [bp] 7 [sp] 16 [argp] 20 [frame] 66
But that insn setting reg 73 has been eliminated according to the LRA
(.194r.reload) dump:
Updating elimination of equiv for reg 73
...
Removing equiv init insn 9 (freq=10000)
9 r73:SI=[argp:DI+0x30]
REG_EQUIV: [argp:DI]
deleting insn with uid = 9.
Choosing alt 0 in insn 15: (0) r
Choosing alt 0 in insn 18: (0) r
Changing pseudo 73 in operand 0 of insn 21 on equiv [argp:DI+0x30]
Choosing alt 0 in insn 21: (0) rm (1) re
Changing pseudo 73 in operand 1 of insn 24 on equiv [argp:DI+0x30]
Choosing alt 1 in insn 24: (0) r (1) rm
Choosing alt 0 in insn 26: (0) =r (1) qm
Choosing alt 1 in insn 27: (0) r (1) rm
Choosing alt 1 in insn 31: (0) m (1) re
You do update the DF_LR sets elsewhere in LRA, so I was wondering if
it is intentional or not to leave the DF_LR sets unchanged after
elimination.
Ciao!
Steven
------------------ 8< ------------------
EXECUTE_IF_SET_IN_SPARSESET (pseudos_live, i)
mark_pseudo_dead (i);
+ {
+ bitmap b = BITMAP_ALLOC (®_obstack);
+ bitmap_copy (b, DF_LR_IN (bb));
+ bitmap_clear_range (b, 0, FIRST_PSEUDO_REGISTER);
+ EXECUTE_IF_SET_IN_BITMAP (DF_LR_IN (bb), FIRST_PSEUDO_REGISTER, j, bi)
+ if (sparseset_bit_p (pseudos_live, j))
+ bitmap_clear_bit (b, j);
+ if (! bitmap_empty_p (b))
+ {
+ fprintf (stderr, "LIVEIN-mismatch in bb %d:\n", bb->index);
+ EXECUTE_IF_SET_IN_BITMAP (DF_LR_IN (bb),
FIRST_PSEUDO_REGISTER, j, bi)
+ if (sparseset_bit_p (pseudos_live, j))
+ fprintf (stderr, "%u, ", j);
+ fprintf (stderr, "\n");
+ bitmap_clear_range (DF_LR_IN (bb), 0, FIRST_PSEUDO_REGISTER);
+ dump_bitmap (stderr, DF_LR_IN (bb));
+ dump_bitmap (stderr, b);
+ gcc_unreachable ();
+ }
+ BITMAP_FREE (b);
+ }
------------------ 8< ------------------
------------------ 8< ------------------
typedef long unsigned int size_t;
union tree_node;
typedef union tree_node *tree;
struct rtx_def;
typedef struct rtx_def *rtx;
struct rtx_def {
union u {
long hwint[1];
} u;
};
typedef struct mem_attrs
{
tree expr;
rtx offset;
rtx size;
int alias;
unsigned int align;
} mem_attrs;
extern void *ggc_alloc_stat (size_t);
typedef struct htab *htab_t;
extern void ** htab_find_slot (htab_t, const void *, int);
static htab_t mem_attrs_htab;
extern unsigned char mode_size[256];
mem_attrs *get_mem_attrs (int, tree, rtx, rtx, unsigned int,
unsigned char, int);
mem_attrs *
get_mem_attrs (int alias, tree expr, rtx offset, rtx size,
unsigned int align, unsigned char addrspace, int mode)
{
mem_attrs attrs;
void **slot;
if (alias == 0
&& (size == 0
|| (mode != 1 && mode_size[mode] == size->u.hwint[0])))
return 0;
attrs.alias = alias;
slot = htab_find_slot (mem_attrs_htab, &attrs, 1);
return (mem_attrs *) *slot;
}
------------------ 8< ------------------
