diff options
| author | nemet <nemet@138bc75d-0d04-0410-961f-82ee72b054a4> | 2006-02-14 17:45:55 +0000 |
|---|---|---|
| committer | nemet <nemet@138bc75d-0d04-0410-961f-82ee72b054a4> | 2006-02-14 17:45:55 +0000 |
| commit | 2ec9725b3a85d7f566c0f8e257c53c5edd2d8989 (patch) | |
| tree | 0f30a432f7d2bcab1915731bfcfe037cbff9249a /gcc/simplify-rtx.c | |
| parent | f3424fe63fb30896267cd3d2ee562399740112b2 (diff) | |
| download | gcc-2ec9725b3a85d7f566c0f8e257c53c5edd2d8989.tar.gz | |
* simplify-rtx.c (simplify_subreg): Combine SUBREG and TRUNCATE.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@110990 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'gcc/simplify-rtx.c')
| -rw-r--r-- | gcc/simplify-rtx.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/gcc/simplify-rtx.c b/gcc/simplify-rtx.c index c949dea1d16..6f4f09b8e09 100644 --- a/gcc/simplify-rtx.c +++ b/gcc/simplify-rtx.c @@ -4426,6 +4426,14 @@ simplify_subreg (enum machine_mode outermode, rtx op, return NULL_RTX; } + /* Merge implicit and explicit truncations. */ + + if (GET_CODE (op) == TRUNCATE + && GET_MODE_SIZE (outermode) < GET_MODE_SIZE (innermode) + && subreg_lowpart_offset (outermode, innermode) == byte) + return simplify_gen_unary (TRUNCATE, outermode, XEXP (op, 0), + GET_MODE (XEXP (op, 0))); + /* SUBREG of a hard register => just change the register number and/or mode. If the hard register is not valid in that mode, suppress this simplification. If the hard register is the stack, |