On 2 July 2014 03:54, Jeff Law <l...@redhat.com> wrote: > On 07/01/14 01:16, Zhenqiang Chen wrote: > >> >> ChangeLog: >> 2014-07-01 Zhenqiang Chen <zhenqiang.c...@linaro.org> >> >> * loop-invariant.c (struct invariant): Add a new member: eqno; >> (find_identical_invariants): Update eqno; >> (create_new_invariant): Init eqno; >> (get_inv_cost): Compute comp_cost wiht eqno; > > s/wiht/with/ > > Do you have a testcase for this? If at all possible I'd like to see some > kind of test to verify that this tracking results in better invariant > selection.
Since the patch bases on the result of rtx_cost, it is hard to design a common test case. A testcase for ARM is added. > With some kind of test and the ChangeLog typo fixed, this is OK. Thanks. Updated and committed @r212256. ChangeLog: 2014-07-03 Zhenqiang Chen <zhenqiang.c...@linaro.org> * loop-invariant.c (struct invariant): Add a new member: eqno; (find_identical_invariants): Update eqno; (create_new_invariant): Init eqno; (get_inv_cost): Compute comp_cost with eqno; testsuite/ChangeLog: 2014-07-03 Zhenqiang Chen <zhenqiang.c...@linaro.org> * gcc.target/arm/identical-invariants.c: New test. diff --git a/gcc/loop-invariant.c b/gcc/loop-invariant.c index d47d461..bd67eb9 100644 --- a/gcc/loop-invariant.c +++ b/gcc/loop-invariant.c @@ -104,6 +104,9 @@ struct invariant /* The number of the invariant with the same value. */ unsigned eqto; + /* The number of invariants which eqto this. */ + unsigned eqno; + /* If we moved the invariant out of the loop, the register that contains its value. */ rtx reg; @@ -498,6 +501,7 @@ find_identical_invariants (invariant_htab_type *eq, struct invariant *inv) struct invariant *dep; rtx expr, set; enum machine_mode mode; + struct invariant *tmp; if (inv->eqto != ~0u) return; @@ -513,7 +517,12 @@ find_identical_invariants (invariant_htab_type *eq, struct invariant *inv) mode = GET_MODE (expr); if (mode == VOIDmode) mode = GET_MODE (SET_DEST (set)); - inv->eqto = find_or_insert_inv (eq, expr, mode, inv)->invno; + + tmp = find_or_insert_inv (eq, expr, mode, inv); + inv->eqto = tmp->invno; + + if (tmp->invno != inv->invno && inv->always_executed) + tmp->eqno++; if (dump_file && inv->eqto != inv->invno) fprintf (dump_file, @@ -1136,7 +1149,7 @@ get_inv_cost (struct invariant *inv, int *comp_cost, unsigned *regs_needed, if (!inv->cheap_address || inv->def->n_addr_uses < inv->def->n_uses) - (*comp_cost) += inv->cost; + (*comp_cost) += inv->cost * inv->eqno; #ifdef STACK_REGS { diff --git a/gcc/testsuite/gcc.target/arm/identical-invariants.c b/gcc/testsuite/gcc.target/arm/identical-invariants.c new file mode 100644 index 0000000..7762ce6 --- /dev/null +++ b/gcc/testsuite/gcc.target/arm/identical-invariants.c @@ -0,0 +1,29 @@ +/* { dg-do compile { target { arm_thumb2_ok } } } */ +/* { dg-options "-O2 -fdump-rtl-loop2_invariant " } */ + +int t1, t2, t3, t4, t5, t6, t7, t8, t9, t10; +extern void foo2 (int *, int *, int *, int *, int *, int *); +extern int foo3 (int, int, int, int, int, int); +int foo (int a, int b, int c, int d) +{ + int i = a; + + for (; i > 0; i += b) + { + if (a > 0x1234567) + foo2 (&t1, &t2, &t3, &t4, &t5, &t6); + foo2 (&t1, &t2, &t3, &t4, &t5, &t6); + if (b > 0x1234567) + foo2 (&t7, &t2, &t8, &t4, &t5, &t6); + foo2 (&t1, &t2, &t3, &t4, &t5, &t6); + if (c > 0x1234567) + foo2 (&t1, &t9, &t10, &t4, &t5, &t6); + t2 = t5 - d; + } + + return foo3 (t1, t2, t3, t4, t5, t6); +} + +/* { dg-final { scan-rtl-dump "Decided to move invariant 0" "loop2_invariant" } } */ +/* { dg-final { cleanup-rtl-dump "loop2_invariant" } } */ +