From 0c314d1ab0636a2253dfc8b4f9f50010210556dc Mon Sep 17 00:00:00 2001 From: Richard Kenner Date: Sat, 22 Jan 1994 15:50:06 -0500 Subject: [PATCH] (num_sign_bit_copies): Ifndef WORD_REGISTER_OPERATIONS, ensure we don't do the wrong thing if X is narrower than MODE. From-SVN: r6403 --- gcc/combine.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/gcc/combine.c b/gcc/combine.c index a71b2018594..729d557c7d8 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -1,5 +1,5 @@ /* Optimize by combining instructions for GNU compiler. - Copyright (C) 1987, 1988, 1992, 1993 Free Software Foundation, Inc. + Copyright (C) 1987, 1988, 1992, 1993, 1994 Free Software Foundation, Inc. This file is part of GNU CC. @@ -6965,6 +6965,14 @@ num_sign_bit_copies (x, mode) return MAX (1, (num_sign_bit_copies (x, GET_MODE (x)) - (GET_MODE_BITSIZE (GET_MODE (x)) - bitwidth))); +#ifndef WORD_REGISTER_OPERATIONS + /* If this machine does not do all register operations on the entire + register and MODE is wider than the mode of X, we can say nothing + at all about the high-order bits. */ + if (GET_MODE (x) != VOIDmode && bitwidth > GET_MODE_BITSIZE (GET_MODE (x))) + return 1; +#endif + switch (code) { case REG: -- 2.30.2