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| author | Richard Kenner <kenner@gcc.gnu.org> | 1993-11-12 08:53:40 -0500 |
|---|---|---|
| committer | Richard Kenner <kenner@gcc.gnu.org> | 1993-11-12 08:53:40 -0500 |
| commit | 0e84b55633a9e926ca9d572057943cc9c3a70761 (patch) | |
| tree | 9b8bc433e411ac3516269c5f92db3375c5b7b605 /gcc | |
| parent | b7d7295b1a15da3599100688c925bff755cea673 (diff) | |
| download | gcc-0e84b55633a9e926ca9d572057943cc9c3a70761.zip gcc-0e84b55633a9e926ca9d572057943cc9c3a70761.tar.gz gcc-0e84b55633a9e926ca9d572057943cc9c3a70761.tar.bz2 | |
(pattern_really_clobbers_lr): Setting a subreg of a mem is valid and safe.
From-SVN: r6074
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/config/arm/arm.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c index f8bc52b..b075207 100644 --- a/gcc/config/arm/arm.c +++ b/gcc/config/arm/arm.c @@ -1552,7 +1552,11 @@ output_ascii_pseudo_op (stream, p, len) /* Try to determine whether a pattern really clobbers the link register. This information is useful when peepholing, so that lr need not be pushed - if we combine a call followed by a return */ + if we combine a call followed by a return. + NOTE: This code does not check for side-effect expressions in a SET_SRC: + such a check should not be needed because these only update an existing + value within a register; the register must still be set elsewhere within + the function. */ static int pattern_really_clobbers_lr (x) @@ -1570,6 +1574,8 @@ rtx x; case SUBREG: if (GET_CODE (XEXP (SET_DEST (x), 0)) == REG) return REGNO (XEXP (SET_DEST (x), 0)) == 14; + if (GET_CODE (XEXP (SET_DEST (x), 0)) == MEM) + return 0; abort (); default: return 0; |