diff options
Diffstat (limited to 'gcc/vr-values.c')
| -rw-r--r-- | gcc/vr-values.c | 92 |
1 files changed, 57 insertions, 35 deletions
diff --git a/gcc/vr-values.c b/gcc/vr-values.c index 88aa672..da0b249 100644 --- a/gcc/vr-values.c +++ b/gcc/vr-values.c @@ -1208,34 +1208,42 @@ vr_values::extract_range_basic (value_range_equiv *vr, gimple *stmt) mini = 0; maxi = 1; goto bitop_builtin; - /* __builtin_c[lt]z* return [0, prec-1], except for + /* __builtin_clz* return [0, prec-1], except for when the argument is 0, but that is undefined behavior. - On many targets where the CLZ RTL or optab value is defined - for 0 the value is prec, so include that in the range - by default. */ + Always handle __builtin_clz* which can be only written + by user as UB on 0 and so [0, prec-1] range, and the internal-fn + calls depending on how CLZ_DEFINED_VALUE_AT_ZERO is defined. */ CASE_CFN_CLZ: arg = gimple_call_arg (stmt, 0); prec = TYPE_PRECISION (TREE_TYPE (arg)); mini = 0; - maxi = prec; + maxi = prec - 1; mode = SCALAR_INT_TYPE_MODE (TREE_TYPE (arg)); - if (optab_handler (clz_optab, mode) != CODE_FOR_nothing - && CLZ_DEFINED_VALUE_AT_ZERO (mode, zerov) - /* Handle only the single common value. */ - && zerov != prec) - /* Magic value to give up, unless vr0 proves - arg is non-zero. */ - mini = -2; + if (gimple_call_internal_p (stmt)) + { + if (optab_handler (clz_optab, mode) != CODE_FOR_nothing + && CLZ_DEFINED_VALUE_AT_ZERO (mode, zerov) == 2) + { + /* Handle only the single common value. */ + if (zerov == prec) + maxi = prec; + /* Magic value to give up, unless vr0 proves + arg is non-zero. */ + else + mini = -2; + } + } if (TREE_CODE (arg) == SSA_NAME) { const value_range_equiv *vr0 = get_value_range (arg); /* From clz of VR_RANGE minimum we can compute result maximum. */ if (vr0->kind () == VR_RANGE - && TREE_CODE (vr0->min ()) == INTEGER_CST) + && TREE_CODE (vr0->min ()) == INTEGER_CST + && integer_nonzerop (vr0->min ())) { maxi = prec - 1 - tree_floor_log2 (vr0->min ()); - if (maxi != prec) + if (mini == -2) mini = 0; } else if (vr0->kind () == VR_ANTI_RANGE @@ -1251,9 +1259,14 @@ vr_values::extract_range_basic (value_range_equiv *vr, gimple *stmt) if (vr0->kind () == VR_RANGE && TREE_CODE (vr0->max ()) == INTEGER_CST) { - mini = prec - 1 - tree_floor_log2 (vr0->max ()); - if (mini == prec) - break; + int newmini = prec - 1 - tree_floor_log2 (vr0->max ()); + if (newmini == prec) + { + if (maxi == prec) + mini = prec; + } + else + mini = newmini; } } if (mini == -2) @@ -1261,27 +1274,30 @@ vr_values::extract_range_basic (value_range_equiv *vr, gimple *stmt) goto bitop_builtin; /* __builtin_ctz* return [0, prec-1], except for when the argument is 0, but that is undefined behavior. - If there is a ctz optab for this mode and - CTZ_DEFINED_VALUE_AT_ZERO, include that in the range, - otherwise just assume 0 won't be seen. */ + Always handle __builtin_ctz* which can be only written + by user as UB on 0 and so [0, prec-1] range, and the internal-fn + calls depending on how CTZ_DEFINED_VALUE_AT_ZERO is defined. */ CASE_CFN_CTZ: arg = gimple_call_arg (stmt, 0); prec = TYPE_PRECISION (TREE_TYPE (arg)); mini = 0; maxi = prec - 1; mode = SCALAR_INT_TYPE_MODE (TREE_TYPE (arg)); - if (optab_handler (ctz_optab, mode) != CODE_FOR_nothing - && CTZ_DEFINED_VALUE_AT_ZERO (mode, zerov)) + if (gimple_call_internal_p (stmt)) { - /* Handle only the two common values. */ - if (zerov == -1) - mini = -1; - else if (zerov == prec) - maxi = prec; - else - /* Magic value to give up, unless vr0 proves - arg is non-zero. */ - mini = -2; + if (optab_handler (ctz_optab, mode) != CODE_FOR_nothing + && CTZ_DEFINED_VALUE_AT_ZERO (mode, zerov) == 2) + { + /* Handle only the two common values. */ + if (zerov == -1) + mini = -1; + else if (zerov == prec) + maxi = prec; + else + /* Magic value to give up, unless vr0 proves + arg is non-zero. */ + mini = -2; + } } if (TREE_CODE (arg) == SSA_NAME) { @@ -1300,10 +1316,16 @@ vr_values::extract_range_basic (value_range_equiv *vr, gimple *stmt) if (vr0->kind () == VR_RANGE && TREE_CODE (vr0->max ()) == INTEGER_CST) { - maxi = tree_floor_log2 (vr0->max ()); - /* For vr0 [0, 0] give up. */ - if (maxi == -1) - break; + int newmaxi = tree_floor_log2 (vr0->max ()); + if (newmaxi == -1) + { + if (mini == -1) + maxi = -1; + else if (maxi == prec) + mini = prec; + } + else if (maxi != prec) + maxi = newmaxi; } } if (mini == -2) |