| Message ID | 20110103143624.GD16156@tyan-ft48-01.lab.bos.redhat.com |
|---|---|
| State | New |
| Headers | show |
On 01/03/2011 03:36 PM, Jakub Jelinek wrote: > Hi! > > If try_combine turns a JUMP_INSN into a noop move, it correctly calls > update_cfg_for_uncondjump on it and sets *new_direct_jump_p if the > noop move is in i3, but as shown on the testcase below, a jump can > be turned into a noop move also when adjusting the only CC user and in that > case we wouldn't do the necessary cfg adjustments. > > Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux, ok for > trunk? Looks good to me. Paolo
> 2011-01-03 Jakub Jelinek <jakub@redhat.com> > > PR rtl-optimization/47157 > * combine.c (try_combine): If undobuf.other_insn becomes > (set (pc) (pc)) jump, call update_cfg_for_uncondjump on it > and set *new_direct_jump_p too. > > * gcc.c-torture/compile/pr47157.c: New test. OK, thanks.
--- gcc/combine.c.jj 2010-12-02 11:51:32.000000000 +0100 +++ gcc/combine.c 2011-01-03 11:07:59.000000000 +0100 @@ -4378,6 +4378,15 @@ try_combine (rtx i3, rtx i2, rtx i1, rtx update_cfg_for_uncondjump (i3); } + if (undobuf.other_insn != NULL_RTX + && GET_CODE (PATTERN (undobuf.other_insn)) == SET + && SET_SRC (PATTERN (undobuf.other_insn)) == pc_rtx + && SET_DEST (PATTERN (undobuf.other_insn)) == pc_rtx) + { + *new_direct_jump_p = 1; + update_cfg_for_uncondjump (undobuf.other_insn); + } + combine_successes++; undo_commit (); --- gcc/testsuite/gcc.c-torture/compile/pr47157.c.jj 2011-01-03 11:21:37.000000000 +0100 +++ gcc/testsuite/gcc.c-torture/compile/pr47157.c 2011-01-03 11:21:17.000000000 +0100 @@ -0,0 +1,20 @@ +/* PR rtl-optimization/47157 */ + +struct S { unsigned a; unsigned b; } c = { 1, 0 }; +unsigned long int e; +void bar (int); +int baz (void); + +static int +foo (int x, short y) +{ + return ((x ^ y) & ((x ^ (x ^ y) & ~__INT_MAX__) - y ^ y)) < 0 ? x : x - y; +} + +void +test (void) +{ + bar (foo (baz () != (c.a | c.b), -1L)); + for (e = 0; e; e = 1) + ; +}