I.e. the arguments after your patch are exactly swapped. This is usually harmless, but not always, so that should be corrected before check in. The change in cselib.c:cselib_invalidate_mem has the same problem.
Well, I have already committed the patch, so attached is a patch to fix things up. Looking at the read MEM canonicalization further, these are obviously canonicalized in cse.c:invalidate, but this is not so clear in cselib. I can see some canonicalization going on where things are recorded, but there is no comment in cselib.h:cselib_val nor cselib.c:first_containing_mem to say that it's guaranteed that all the expression in the locs lists are canonicalized, so I'll assume that's not a safe assumption, and I've added an mem_canonicalized parameter to canon_anti_dependence to indicate if MEM (the previously read location) is canonicalized. Bootstrapped / regtested on i686-pc-linux-gnu.
2013-06-19 Joern Rennecke <joern.renne...@embecosm.com> PR rtl-optimization/57425 PR rtl-optimization/57569 * alias.c (write_dependence_p): Remove parameters mem_mode and canon_mem_addr. Add parameters x_mode, x_addr and x_canonicalized. Changed all callers. (canon_anti_dependence): Get comments and semantics in sync, to be a proper drop-in replacement for canon_true_dependence for use by cse(lib). Add parameter mem_canonicalized. Changed all callers. * rtl.h (canon_anti_dependence): Update prototype. Index: alias.c =================================================================== --- alias.c (revision 200133) +++ alias.c (working copy) @@ -156,8 +156,9 @@ static int insert_subset_children (splay static alias_set_entry get_alias_set_entry (alias_set_type); static bool nonoverlapping_component_refs_p (const_rtx, const_rtx); static tree decl_for_component_ref (tree); -static int write_dependence_p (const_rtx, enum machine_mode, rtx, const_rtx, - bool, bool); +static int write_dependence_p (const_rtx, + const_rtx, enum machine_mode, rtx, + bool, bool, bool); static void memory_modified_1 (rtx, const_rtx, void *); @@ -2555,20 +2556,22 @@ canon_true_dependence (const_rtx mem, en /* Returns nonzero if a write to X might alias a previous read from (or, if WRITEP is true, a write to) MEM. - If MEM_CANONCALIZED is nonzero, CANON_MEM_ADDR is the canonicalized - address of MEM, and MEM_MODE the mode for that access. */ + If X_CANONCALIZED is nonzero, then X_ADDR is the canonicalized address of X, + and X_MODE the mode for that access. + If MEM_CANONICALIZED is true, MEM is canonicalized. */ static int -write_dependence_p (const_rtx mem, enum machine_mode mem_mode, - rtx canon_mem_addr, const_rtx x, - bool mem_canonicalized, bool writep) +write_dependence_p (const_rtx mem, + const_rtx x, enum machine_mode x_mode, rtx x_addr, + bool mem_canonicalized, bool x_canonicalized, bool writep) { - rtx x_addr, mem_addr; + rtx mem_addr; rtx base; int ret; - gcc_checking_assert (mem_canonicalized ? (canon_mem_addr != NULL_RTX) - : (canon_mem_addr == NULL_RTX && mem_mode == VOIDmode)); + gcc_checking_assert (x_canonicalized + ? (x_addr != NULL_RTX && x_mode != VOIDmode) + : (x_addr == NULL_RTX && x_mode == VOIDmode)); if (MEM_VOLATILE_P (x) && MEM_VOLATILE_P (mem)) return 1; @@ -2593,17 +2596,21 @@ write_dependence_p (const_rtx mem, enum if (MEM_ADDR_SPACE (mem) != MEM_ADDR_SPACE (x)) return 1; - x_addr = XEXP (x, 0); mem_addr = XEXP (mem, 0); - if (!((GET_CODE (x_addr) == VALUE - && GET_CODE (mem_addr) != VALUE - && reg_mentioned_p (x_addr, mem_addr)) - || (GET_CODE (x_addr) != VALUE - && GET_CODE (mem_addr) == VALUE - && reg_mentioned_p (mem_addr, x_addr)))) + if (!x_addr) { - x_addr = get_addr (x_addr); - mem_addr = get_addr (mem_addr); + x_addr = XEXP (x, 0); + if (!((GET_CODE (x_addr) == VALUE + && GET_CODE (mem_addr) != VALUE + && reg_mentioned_p (x_addr, mem_addr)) + || (GET_CODE (x_addr) != VALUE + && GET_CODE (mem_addr) == VALUE + && reg_mentioned_p (mem_addr, x_addr)))) + { + x_addr = get_addr (x_addr); + if (!mem_canonicalized) + mem_addr = get_addr (mem_addr); + } } base = find_base_term (mem_addr); @@ -2619,17 +2626,16 @@ write_dependence_p (const_rtx mem, enum GET_MODE (mem))) return 0; - x_addr = canon_rtx (x_addr); - if (mem_canonicalized) - mem_addr = canon_mem_addr; - else + if (!x_canonicalized) { - mem_addr = canon_rtx (mem_addr); - mem_mode = GET_MODE (mem); + x_addr = canon_rtx (x_addr); + x_mode = GET_MODE (x); } + if (!mem_canonicalized) + mem_addr = canon_rtx (mem_addr); - if ((ret = memrefs_conflict_p (GET_MODE_SIZE (mem_mode), mem_addr, - SIZE_FOR_MODE (x), x_addr, 0)) != -1) + if ((ret = memrefs_conflict_p (SIZE_FOR_MODE (mem), mem_addr, + GET_MODE_SIZE (x_mode), x_addr, 0)) != -1) return ret; if (nonoverlapping_memrefs_p (x, mem, false)) @@ -2643,20 +2649,24 @@ write_dependence_p (const_rtx mem, enum int anti_dependence (const_rtx mem, const_rtx x) { - return write_dependence_p (mem, VOIDmode, NULL_RTX, x, - /*mem_canonicalized=*/false, /*writep=*/false); + return write_dependence_p (mem, x, VOIDmode, NULL_RTX, + /*mem_canonicalized=*/false, + /*x_canonicalized*/false, /*writep=*/false); } -/* Likewise, but we already have a canonicalized MEM_ADDR for MEM. - Also, consider MEM in MEM_MODE (which might be from an enclosing - STRICT_LOW_PART / ZERO_EXTRACT). */ +/* Likewise, but we already have a canonicalized MEM, and X_ADDR for X. + Also, consider X in X_MODE (which might be from an enclosing + STRICT_LOW_PART / ZERO_EXTRACT). + If X_CANONICALIZED is true, X is canonicalized. + The argument order is adjusted to mostly match canon_true_dependence. */ int -canon_anti_dependence (const_rtx mem, enum machine_mode mem_mode, - rtx mem_addr, const_rtx x) +canon_anti_dependence (const_rtx x, enum machine_mode x_mode, rtx x_addr, + const_rtx mem, bool mem_canonicalized) { - return write_dependence_p (mem, mem_mode, mem_addr, x, - /*mem_canonicalized=*/true, /*writep=*/false); + return write_dependence_p (mem, x, x_mode, x_addr, + mem_canonicalized, /*x_canonicalized=*/true, + /*writep=*/false); } /* Output dependence: X is written after store in MEM takes place. */ @@ -2664,8 +2674,9 @@ canon_anti_dependence (const_rtx mem, en int output_dependence (const_rtx mem, const_rtx x) { - return write_dependence_p (mem, VOIDmode, NULL_RTX, x, - /*mem_canonicalized=*/false, /*writep=*/true); + return write_dependence_p (mem, x, VOIDmode, NULL_RTX, + /*mem_canonicalized=*/false, + /*x_canonicalized*/false, /*writep=*/true); } Index: cse.c =================================================================== --- cse.c (revision 200133) +++ cse.c (working copy) @@ -1837,7 +1837,7 @@ check_dependence (rtx *x, void *data) { struct check_dependence_data *d = (struct check_dependence_data *) data; if (*x && MEM_P (*x)) - return canon_anti_dependence (d->exp, d->mode, d->addr, *x); + return canon_anti_dependence (d->exp, d->mode, d->addr, *x, true); else return 0; } Index: cselib.c =================================================================== --- cselib.c (revision 200133) +++ cselib.c (working copy) @@ -2264,7 +2264,7 @@ cselib_invalidate_mem (rtx mem_rtx) } if (num_mems < PARAM_VALUE (PARAM_MAX_CSELIB_MEMORY_LOCATIONS) && ! canon_anti_dependence (mem_rtx, GET_MODE (mem_rtx), - mem_addr, x)) + mem_addr, x, false)) { has_mem = true; num_mems++; Index: rtl.h =================================================================== --- rtl.h (revision 200133) +++ rtl.h (working copy) @@ -2706,7 +2706,7 @@ extern int canon_true_dependence (const_ extern int read_dependence (const_rtx, const_rtx); extern int anti_dependence (const_rtx, const_rtx); extern int canon_anti_dependence (const_rtx, enum machine_mode, rtx, - const_rtx); + const_rtx, bool); extern int output_dependence (const_rtx, const_rtx); extern int may_alias_p (const_rtx, const_rtx); extern void init_alias_target (void);