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| author | rth <rth@138bc75d-0d04-0410-961f-82ee72b054a4> | 2003-02-05 22:37:54 +0000 |
|---|---|---|
| committer | rth <rth@138bc75d-0d04-0410-961f-82ee72b054a4> | 2003-02-05 22:37:54 +0000 |
| commit | 8f4be2be97089ba0dc22ed55ee33d90e237b8c1e (patch) | |
| tree | e14ea46575bce454a67edbb9d6bc03000c970bcd /gcc/fold-const.c | |
| parent | 3b51cb387e3c601a6663f518b402c09c6b69eeb5 (diff) | |
| download | gcc-8f4be2be97089ba0dc22ed55ee33d90e237b8c1e.tar.gz | |
* defaults.h (CLZ_DEFINED_VALUE_AT_ZERO): New.
(CTZ_DEFINED_VALUE_AT_ZERO): New.
* doc/rtl.texi, doc/tm.texi: Document them.
* combine.c (nonzero_bits) [CLZ, CTZ]: Handle the definedness
of the value at zero properly.
* fold-const.c (tree_expr_nonnegative_p): Likewise.
* simplify-rtx.c (simplify_unary_operation): Likewise.
* config/alpha/alpha.h (CLZ_DEFINED_VALUE_AT_ZERO): New.
(CTZ_DEFINED_VALUE_AT_ZERO): New.
* config/arm/arm.c (TARGET_INIT_BUILTINS): Remove.
(TARGET_EXPAND_BUILTIN): Remove.
(def_builtin, arm_init_builtins, arm_expand_builtin): Remove.
* config/arm/arm.h (CLZ_DEFINED_VALUE_AT_ZERO): New.
(enum arm_builtins): Remove.
* config/arm/arm.md (UNSPEC_CLZ): Remove.
(clzsi2): Rename from clz; use clz instead of unspec.
(ctzsi2): New.
* config/arm/arm-protos.h: Update.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@62453 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'gcc/fold-const.c')
| -rw-r--r-- | gcc/fold-const.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/gcc/fold-const.c b/gcc/fold-const.c index 55f4ce46c41..0e301a72690 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -7436,11 +7436,17 @@ tree_expr_nonnegative_p (t) { case ABS_EXPR: case FFS_EXPR: - case CLZ_EXPR: - case CTZ_EXPR: case POPCOUNT_EXPR: case PARITY_EXPR: return 1; + + case CLZ_EXPR: + case CTZ_EXPR: + /* These are undefined at zero. This is true even if + C[LT]Z_DEFINED_VALUE_AT_ZERO is set, since what we're + computing here is a user-visible property. */ + return 0; + case INTEGER_CST: return tree_int_cst_sgn (t) >= 0; case TRUNC_DIV_EXPR: |