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| author | Aldy Hernandez <aldyh@redhat.com> | 2012-10-17 20:59:40 +0000 |
|---|---|---|
| committer | Aldy Hernandez <aldyh@gcc.gnu.org> | 2012-10-17 20:59:40 +0000 |
| commit | a7b159a4dcca7e45fdf2b57a865dd2a91148eefb (patch) | |
| tree | 6246e46226dfe3ca8100baf6e693f108a7fa2483 /gcc | |
| parent | 4d9675496a28ef6184f2a9c3ac5e6e3ea63606c1 (diff) | |
| download | gcc-a7b159a4dcca7e45fdf2b57a865dd2a91148eefb.zip gcc-a7b159a4dcca7e45fdf2b57a865dd2a91148eefb.tar.gz gcc-a7b159a4dcca7e45fdf2b57a865dd2a91148eefb.tar.bz2 | |
re PR rtl-optimization/54900 (write introduction incorrect wrt the C11 memory model (2))
PR rtl-optimization/54900
* ifcvt.c (noce_can_store_speculate_p): Call
memory_must_be_modified_in_insn_p.
* alias.c (memory_must_be_modified_in_insn_p): New.
(set_dest_equal_p): New.
* rtl.h (memory_must_be_modified_in_p): Protoize.
From-SVN: r192548
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 9 | ||||
| -rw-r--r-- | gcc/alias.c | 33 | ||||
| -rw-r--r-- | gcc/ifcvt.c | 2 | ||||
| -rw-r--r-- | gcc/rtl.h | 1 |
4 files changed, 44 insertions, 1 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 6571fdc..9c6a1d9 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,12 @@ +2012-10-17 Aldy Hernandez <aldyh@redhat.com> + + PR rtl-optimization/54900 + * ifcvt.c (noce_can_store_speculate_p): Call + memory_must_be_modified_in_insn_p. + * alias.c (memory_must_be_modified_in_insn_p): New. + (set_dest_equal_p): New. + * rtl.h (memory_must_be_modified_in_p): Protoize. + 2012-10-17 Michael Meissner <meissner@linux.vnet.ibm.com> * config/rs6000/rs6000.opt (rs6000_isa_flags): New flag word to diff --git a/gcc/alias.c b/gcc/alias.c index 244ca52..c5e6417 100644 --- a/gcc/alias.c +++ b/gcc/alias.c @@ -2762,6 +2762,39 @@ memory_modified_in_insn_p (const_rtx mem, const_rtx insn) return memory_modified; } +/* Return TRUE if the destination of a set is rtx identical to + ITEM. */ +static inline bool +set_dest_equal_p (const_rtx set, const_rtx item) +{ + rtx dest = SET_DEST (set); + return rtx_equal_p (dest, item); +} + +/* Like memory_modified_in_insn_p, but return TRUE if INSN will + *DEFINITELY* modify the memory contents of MEM. */ +bool +memory_must_be_modified_in_insn_p (const_rtx mem, const_rtx insn) +{ + if (!INSN_P (insn)) + return false; + insn = PATTERN (insn); + if (GET_CODE (insn) == SET) + return set_dest_equal_p (insn, mem); + else if (GET_CODE (insn) == PARALLEL) + { + int i; + for (i = 0; i < XVECLEN (insn, 0); i++) + { + rtx sub = XVECEXP (insn, 0, i); + if (GET_CODE (sub) == SET + && set_dest_equal_p (sub, mem)) + return true; + } + } + return false; +} + /* Initialize the aliasing machinery. Initialize the REG_KNOWN_VALUE array. */ diff --git a/gcc/ifcvt.c b/gcc/ifcvt.c index 2f486a2..5654c66 100644 --- a/gcc/ifcvt.c +++ b/gcc/ifcvt.c @@ -2415,7 +2415,7 @@ noce_can_store_speculate_p (basic_block top_bb, const_rtx mem) || (CALL_P (insn) && (!RTL_CONST_CALL_P (insn))))) return false; - if (memory_modified_in_insn_p (mem, insn)) + if (memory_must_be_modified_in_insn_p (mem, insn)) return true; if (modified_in_p (XEXP (mem, 0), insn)) return false; @@ -2616,6 +2616,7 @@ extern void init_alias_analysis (void); extern void end_alias_analysis (void); extern void vt_equate_reg_base_value (const_rtx, const_rtx); extern bool memory_modified_in_insn_p (const_rtx, const_rtx); +extern bool memory_must_be_modified_in_insn_p (const_rtx, const_rtx); extern bool may_be_sp_based_p (rtx); extern rtx gen_hard_reg_clobber (enum machine_mode, unsigned int); extern rtx get_reg_known_value (unsigned int); |