diff options
author | Yvan Roux <yvan.roux@linaro.org> | 2016-09-05 19:00:39 +0200 |
---|---|---|
committer | Yvan Roux <yvan.roux@linaro.org> | 2016-09-07 22:08:53 +0200 |
commit | a948d918d75bbcc1a5a97d297d3a71494eeeafc8 (patch) | |
tree | ad31256374cfe8e5fa7d52d505ffc26f2dd67000 | |
parent | 33d29b1c6ba8dcddc080d842aafefa9bfb6982d0 (diff) |
gcc/
Backport from trunk r238013.
2016-07-05 Kyrylo Tkachov <kyrylo.tkachov@arm.com>
PR rtl-optimization/71594
* ifcvt.c (noce_convert_multiple_sets): Wrap new_val or old_val
into subregs of appropriate mode before trying to emit a conditional
move.
gcc/testsuite/
Backport from trunk r238013.
2016-07-05 Kyrylo Tkachov <kyrylo.tkachov@arm.com>
PR rtl-optimization/71594
* gcc.dg/torture/pr71594.c: New test.
Change-Id: I0ee49c3987adc7ee7ef5d4d6baf9712e3659f885
-rw-r--r-- | gcc/ifcvt.c | 35 | ||||
-rw-r--r-- | gcc/testsuite/gcc.dg/torture/pr71594.c | 15 |
2 files changed, 50 insertions, 0 deletions
diff --git a/gcc/ifcvt.c b/gcc/ifcvt.c index 4a277db7dcc..95d38107b86 100644 --- a/gcc/ifcvt.c +++ b/gcc/ifcvt.c @@ -3228,6 +3228,41 @@ noce_convert_multiple_sets (struct noce_if_info *if_info) if (if_info->then_else_reversed) std::swap (old_val, new_val); + + /* We allow simple lowpart register subreg SET sources in + bb_ok_for_noce_convert_multiple_sets. Be careful when processing + sequences like: + (set (reg:SI r1) (reg:SI r2)) + (set (reg:HI r3) (subreg:HI (r1))) + For the second insn new_val or old_val (r1 in this example) will be + taken from the temporaries and have the wider mode which will not + match with the mode of the other source of the conditional move, so + we'll end up trying to emit r4:HI = cond ? (r1:SI) : (r3:HI). + Wrap the two cmove operands into subregs if appropriate to prevent + that. */ + if (GET_MODE (new_val) != GET_MODE (temp)) + { + machine_mode src_mode = GET_MODE (new_val); + machine_mode dst_mode = GET_MODE (temp); + if (GET_MODE_SIZE (src_mode) <= GET_MODE_SIZE (dst_mode)) + { + end_sequence (); + return FALSE; + } + new_val = lowpart_subreg (dst_mode, new_val, src_mode); + } + if (GET_MODE (old_val) != GET_MODE (temp)) + { + machine_mode src_mode = GET_MODE (old_val); + machine_mode dst_mode = GET_MODE (temp); + if (GET_MODE_SIZE (src_mode) <= GET_MODE_SIZE (dst_mode)) + { + end_sequence (); + return FALSE; + } + old_val = lowpart_subreg (dst_mode, old_val, src_mode); + } + /* Actually emit the conditional move. */ rtx temp_dest = noce_emit_cmove (if_info, temp, cond_code, x, y, new_val, old_val); diff --git a/gcc/testsuite/gcc.dg/torture/pr71594.c b/gcc/testsuite/gcc.dg/torture/pr71594.c new file mode 100644 index 00000000000..468a9f6891c --- /dev/null +++ b/gcc/testsuite/gcc.dg/torture/pr71594.c @@ -0,0 +1,15 @@ +/* { dg-do compile } */ +/* { dg-options "--param max-rtl-if-conversion-insns=2" } */ + +unsigned short a; +int b, c; +int *d; +void fn1() { + *d = 24; + for (; *d <= 65;) { + unsigned short *e = &a; + b = (a &= 0 <= 0) < (c ?: (*e %= *d)); + for (; *d <= 83;) + ; + } +} |