From fae2db4744dd199c7aea8cf48b3ab7a1282e98cc Mon Sep 17 00:00:00 2001 From: Jim Wilson Date: Mon, 2 Aug 1999 23:53:14 +0000 Subject: Optimize duplicate zero_extend operations. * combine.c (force_to_mode, case LSHIFTRT): Add goto shiftrt. (force_to_mode, case ASHIFTRT): Add shiftrt label. From-SVN: r28424 --- gcc/combine.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'gcc/combine.c') diff --git a/gcc/combine.c b/gcc/combine.c index c9736e5..c922c86 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -6574,7 +6574,8 @@ force_to_mode (x, mode, mask, reg, just_select) x = gen_binary (LSHIFTRT, GET_MODE (x), XEXP (x, 0), GEN_INT (GET_MODE_BITSIZE (GET_MODE (x)) - exact_log2 (mask + 1))); - break; + + goto shiftrt; case ASHIFTRT: /* If we are just looking for the sign bit, we don't need this shift at @@ -6639,7 +6640,9 @@ force_to_mode (x, mode, mask, reg, just_select) if (mask == 1) x = gen_binary (LSHIFTRT, GET_MODE (x), XEXP (x, 0), XEXP (x, 1)); - /* If this is a sign-extension operation that just affects bits + shiftrt: + + /* If this is a zero- or sign-extension operation that just affects bits we don't care about, remove it. Be sure the call above returned something that is still a shift. */ -- cgit v1.1