diff options
| author | sayle <sayle@138bc75d-0d04-0410-961f-82ee72b054a4> | 2005-01-14 04:17:13 +0000 |
|---|---|---|
| committer | sayle <sayle@138bc75d-0d04-0410-961f-82ee72b054a4> | 2005-01-14 04:17:13 +0000 |
| commit | a3715b0064fd8593f1898ae6adb7274522f1f5f5 (patch) | |
| tree | 219dd8772e524e69adedf45921c3ce4d94414a50 /gcc/simplify-rtx.c | |
| parent | 7269ed388b799b14475ab545613bcd01b37632ef (diff) | |
| download | gcc-a3715b0064fd8593f1898ae6adb7274522f1f5f5.tar.gz | |
* simplify-rtx.c (simplify_binary_operation) <AND>: Optimize
(and (sign_extend X) C) into (zero_extend (and X C)).
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@93629 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'gcc/simplify-rtx.c')
| -rw-r--r-- | gcc/simplify-rtx.c | 19 |
1 files changed, 18 insertions, 1 deletions
diff --git a/gcc/simplify-rtx.c b/gcc/simplify-rtx.c index 0aa1e9576aa..91df355b9ac 100644 --- a/gcc/simplify-rtx.c +++ b/gcc/simplify-rtx.c @@ -1,6 +1,6 @@ /* RTL simplification functions for GNU compiler. Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998, - 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc. + 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc. This file is part of GCC. @@ -1910,6 +1910,23 @@ simplify_binary_operation (enum rtx_code code, enum machine_mode mode, && ! side_effects_p (op0) && GET_MODE_CLASS (mode) != MODE_CC) return const0_rtx; + + /* Transform (and (extend X) C) into (zero_extend (and X C)) if + there are no non-zero bits of C outside of X's mode. */ + if ((GET_CODE (op0) == SIGN_EXTEND + || GET_CODE (op0) == ZERO_EXTEND) + && GET_CODE (trueop1) == CONST_INT + && GET_MODE_BITSIZE (mode) <= HOST_BITS_PER_WIDE_INT + && (~GET_MODE_MASK (GET_MODE (XEXP (op0, 0))) + & INTVAL (trueop1)) == 0) + { + enum machine_mode imode = GET_MODE (XEXP (op0, 0)); + tem = simplify_gen_binary (AND, imode, XEXP (op0, 0), + gen_int_mode (INTVAL (trueop1), + imode)); + return simplify_gen_unary (ZERO_EXTEND, mode, tem, imode); + } + /* For constants M and N, if M == (1LL << cst) - 1 && (N & M) == M, ((A & N) + B) & M -> (A + B) & M Similarly if (N & M) == 0, |