This commit is contained in:
Jakub Jelinek 2009-09-09 09:06:01 +00:00
parent 116cffef39
commit 38ba9bfb90

View File

@ -0,0 +1,188 @@
for gcc/ChangeLog
from Alexandre Oliva <aoliva@redhat.com>
PR debug/41276
PR debug/41307
* cselib.c (cselib_expand_value_rtx_cb): Document callback
interface.
(cselib_expand_value_rtx_1): Use callback for SUBREGs. Adjust
for VALUEs, to implement the documented interface.
* var-tracking.c (vt_expand_loc_callback): Handle SUBREGs.
Adjust for VALUEs and anything else, to implement the
documented interface.
Index: gcc/cselib.c
===================================================================
--- gcc/cselib.c.orig 2009-09-08 19:34:10.000000000 -0300
+++ gcc/cselib.c 2009-09-09 05:20:52.000000000 -0300
@@ -1053,7 +1053,10 @@ cselib_expand_value_rtx (rtx orig, bitma
}
/* Same as cselib_expand_value_rtx, but using a callback to try to
- resolve VALUEs that expand to nothing. */
+ resolve some expressions. The CB function should return ORIG if it
+ can't or does not want to deal with a certain RTX. Any other
+ return value, including NULL, will be used as the expansion for
+ VALUE, without any further changes. */
rtx
cselib_expand_value_rtx_cb (rtx orig, bitmap regs_active, int max_depth,
@@ -1068,6 +1071,9 @@ cselib_expand_value_rtx_cb (rtx orig, bi
return cselib_expand_value_rtx_1 (orig, &evd, max_depth);
}
+/* Internal implementation of cselib_expand_value_rtx and
+ cselib_expand_value_rtx_cb. */
+
static rtx
cselib_expand_value_rtx_1 (rtx orig, struct expand_value_data *evd,
int max_depth)
@@ -1158,26 +1164,36 @@ cselib_expand_value_rtx_1 (rtx orig, str
case SUBREG:
{
- rtx subreg = cselib_expand_value_rtx_1 (SUBREG_REG (orig), evd,
- max_depth - 1);
+ rtx subreg;
+
+ if (evd->callback)
+ {
+ subreg = evd->callback (orig, evd->regs_active, max_depth,
+ evd->callback_arg);
+ if (subreg != orig)
+ return subreg;
+ }
+
+ subreg = cselib_expand_value_rtx_1 (SUBREG_REG (orig), evd,
+ max_depth - 1);
if (!subreg)
return NULL;
scopy = simplify_gen_subreg (GET_MODE (orig), subreg,
GET_MODE (SUBREG_REG (orig)),
SUBREG_BYTE (orig));
- if ((scopy == NULL
- || (GET_CODE (scopy) == SUBREG
- && !REG_P (SUBREG_REG (scopy))
- && !MEM_P (SUBREG_REG (scopy))))
- && (REG_P (SUBREG_REG (orig))
- || MEM_P (SUBREG_REG (orig))))
- return shallow_copy_rtx (orig);
+ if (scopy == NULL
+ || (GET_CODE (scopy) == SUBREG
+ && !REG_P (SUBREG_REG (scopy))
+ && !MEM_P (SUBREG_REG (scopy))))
+ return NULL;
+
return scopy;
}
case VALUE:
{
rtx result;
+
if (dump_file && (dump_flags & TDF_DETAILS))
{
fputs ("\nexpanding ", dump_file);
@@ -1185,20 +1201,16 @@ cselib_expand_value_rtx_1 (rtx orig, str
fputs (" into...", dump_file);
}
- if (!evd->callback)
- result = NULL;
- else
+ if (evd->callback)
{
result = evd->callback (orig, evd->regs_active, max_depth,
evd->callback_arg);
- if (result == orig)
- result = NULL;
- else if (result)
- result = cselib_expand_value_rtx_1 (result, evd, max_depth);
+
+ if (result != orig)
+ return result;
}
- if (!result)
- result = expand_loc (CSELIB_VAL_PTR (orig)->locs, evd, max_depth);
+ result = expand_loc (CSELIB_VAL_PTR (orig)->locs, evd, max_depth);
return result;
}
default:
Index: gcc/var-tracking.c
===================================================================
--- gcc/var-tracking.c.orig 2009-09-08 19:33:55.000000000 -0300
+++ gcc/var-tracking.c 2009-09-08 20:08:08.000000000 -0300
@@ -6243,7 +6243,8 @@ check_wrap_constant (enum machine_mode m
}
/* Callback for cselib_expand_value, that looks for expressions
- holding the value in the var-tracking hash tables. */
+ holding the value in the var-tracking hash tables. Return X for
+ standard processing, anything else is to be used as-is. */
static rtx
vt_expand_loc_callback (rtx x, bitmap regs, int max_depth, void *data)
@@ -6254,19 +6255,46 @@ vt_expand_loc_callback (rtx x, bitmap re
location_chain loc;
rtx result;
- gcc_assert (GET_CODE (x) == VALUE);
+ if (GET_CODE (x) == SUBREG)
+ {
+ rtx subreg = SUBREG_REG (x);
+
+ if (GET_CODE (SUBREG_REG (x)) != VALUE)
+ return x;
+
+ subreg = cselib_expand_value_rtx_cb (SUBREG_REG (x), regs,
+ max_depth - 1,
+ vt_expand_loc_callback, data);
+
+ if (!subreg)
+ return NULL;
+
+ result = simplify_gen_subreg (GET_MODE (x), subreg,
+ GET_MODE (SUBREG_REG (x)),
+ SUBREG_BYTE (x));
+
+ /* Invalid SUBREGs are ok in debug info. ??? We could try
+ alternate expansions for the VALUE as well. */
+ if (!result && (REG_P (subreg) || MEM_P (subreg)))
+ result = gen_rtx_raw_SUBREG (GET_MODE (x), subreg, SUBREG_BYTE (x));
+
+ return result;
+ }
+
+ if (GET_CODE (x) != VALUE)
+ return x;
if (VALUE_RECURSED_INTO (x))
- return NULL;
+ return x;
dv = dv_from_value (x);
var = (variable) htab_find_with_hash (vars, dv, dv_htab_hash (dv));
if (!var)
- return NULL;
+ return x;
if (var->n_var_parts == 0)
- return NULL;
+ return x;
gcc_assert (var->n_var_parts == 1);
@@ -6283,7 +6311,10 @@ vt_expand_loc_callback (rtx x, bitmap re
}
VALUE_RECURSED_INTO (x) = false;
- return result;
+ if (result)
+ return result;
+ else
+ return x;
}
/* Expand VALUEs in LOC, using VARS as well as cselib's equivalence