From ae1669a98656cca594fcd2fef6bd2cd7308a361f Mon Sep 17 00:00:00 2001
From: Andrew MacLeod <amacleod@redhat.com>
Date: Tue, 20 Sep 2022 18:12:25 -0400
Subject: [PATCH 11/17] Convert CFN_CLZ builtins to range-ops.
* gimple-range-fold.cc (range_of_builtin_int_call): Remove case
for CFN_CLZ.
* gimple-range-op.cc (class cfn_clz): New.
(gimple_range_op_handler::maybe_builtin_call): Set arguments.
---
gcc/gimple-range-fold.cc | 61 -----------------------------
gcc/gimple-range-op.cc | 84 ++++++++++++++++++++++++++++++++++++++++
2 files changed, 84 insertions(+), 61 deletions(-)
@@ -926,67 +926,6 @@ fold_using_range::range_of_builtin_int_call (irange &r, gcall *call,
r.set (build_zero_cst (type), build_one_cst (type));
return true;
- CASE_CFN_CLZ:
- // __builtin_c[lt]z* return [0, prec-1], except when the
- // argument is 0, but that is undefined behavior.
- //
- // For __builtin_c[lt]z* consider argument of 0 always undefined
- // behavior, for internal fns depending on C?Z_DEFINED_VALUE_AT_ZERO.
- arg = gimple_call_arg (call, 0);
- prec = TYPE_PRECISION (TREE_TYPE (arg));
- mini = 0;
- maxi = prec - 1;
- mode = SCALAR_INT_TYPE_MODE (TREE_TYPE (arg));
- if (gimple_call_internal_p (call))
- {
- if (optab_handler (clz_optab, mode) != CODE_FOR_nothing
- && CLZ_DEFINED_VALUE_AT_ZERO (mode, zerov) == 2)
- {
- // Only handle the single common value.
- if (zerov == prec)
- maxi = prec;
- else
- // Magic value to give up, unless we can prove arg is non-zero.
- mini = -2;
- }
- }
-
- src.get_operand (r, arg);
- // From clz of minimum we can compute result maximum.
- if (!r.undefined_p ())
- {
- // From clz of minimum we can compute result maximum.
- if (wi::gt_p (r.lower_bound (), 0, TYPE_SIGN (r.type ())))
- {
- maxi = prec - 1 - wi::floor_log2 (r.lower_bound ());
- if (mini == -2)
- mini = 0;
- }
- else if (!range_includes_zero_p (&r))
- {
- mini = 0;
- maxi = prec - 1;
- }
- if (mini == -2)
- break;
- // From clz of maximum we can compute result minimum.
- wide_int max = r.upper_bound ();
- int newmini = prec - 1 - wi::floor_log2 (max);
- if (max == 0)
- {
- // If CLZ_DEFINED_VALUE_AT_ZERO is 2 with VALUE of prec,
- // return [prec, prec], otherwise ignore the range.
- if (maxi == prec)
- mini = prec;
- }
- else
- mini = newmini;
- }
- if (mini == -2)
- break;
- r.set (build_int_cst (type, mini), build_int_cst (type, maxi));
- return true;
-
CASE_CFN_CTZ:
// __builtin_ctz* return [0, prec-1], except for when the
// argument is 0, but that is undefined behavior.
@@ -414,6 +414,81 @@ public:
}
} op_cfn_popcount;
+// Implement range operator for CFN_BUILT_IN_CLZ
+class cfn_clz : public range_operator
+{
+public:
+ cfn_clz (bool internal) { m_gimple_call_internal_p = internal; }
+ using range_operator::fold_range;
+ virtual bool fold_range (irange &r, tree type, const irange &lh,
+ const irange &, relation_kind) const;
+private:
+ bool m_gimple_call_internal_p;
+} op_cfn_clz (false), op_cfn_clz_internal (true);
+
+bool
+cfn_clz::fold_range (irange &r, tree type, const irange &lh,
+ const irange &, relation_kind) const
+{
+ // __builtin_c[lt]z* return [0, prec-1], except when the
+ // argument is 0, but that is undefined behavior.
+ //
+ // For __builtin_c[lt]z* consider argument of 0 always undefined
+ // behavior, for internal fns depending on C?Z_DEFINED_ALUE_AT_ZERO.
+ if (lh.undefined_p ())
+ return false;
+ int prec = TYPE_PRECISION (lh.type ());
+ int mini = 0;
+ int maxi = prec - 1;
+ int zerov = 0;
+ scalar_int_mode mode = SCALAR_INT_TYPE_MODE (lh.type ());
+ if (m_gimple_call_internal_p)
+ {
+ if (optab_handler (clz_optab, mode) != CODE_FOR_nothing
+ && CLZ_DEFINED_VALUE_AT_ZERO (mode, zerov) == 2)
+ {
+ // Only handle the single common value.
+ if (zerov == prec)
+ maxi = prec;
+ else
+ // Magic value to give up, unless we can prove arg is non-zero.
+ mini = -2;
+ }
+ }
+
+ // From clz of minimum we can compute result maximum.
+ if (wi::gt_p (lh.lower_bound (), 0, TYPE_SIGN (lh.type ())))
+ {
+ maxi = prec - 1 - wi::floor_log2 (lh.lower_bound ());
+ if (mini == -2)
+ mini = 0;
+ }
+ else if (!range_includes_zero_p (&lh))
+ {
+ mini = 0;
+ maxi = prec - 1;
+ }
+ if (mini == -2)
+ return false;
+ // From clz of maximum we can compute result minimum.
+ wide_int max = lh.upper_bound ();
+ int newmini = prec - 1 - wi::floor_log2 (max);
+ if (max == 0)
+ {
+ // If CLZ_DEFINED_VALUE_AT_ZERO is 2 with VALUE of prec,
+ // return [prec, prec], otherwise ignore the range.
+ if (maxi == prec)
+ mini = prec;
+ }
+ else
+ mini = newmini;
+
+ if (mini == -2)
+ return false;
+ r.set (build_int_cst (type, mini), build_int_cst (type, maxi));
+ return true;
+}
+
// Set up a gimple_range_op_handler for any built in function which can be
// supported via range-ops.
@@ -469,6 +544,15 @@ gimple_range_op_handler::maybe_builtin_call ()
m_valid = true;
break;
+ CASE_CFN_CLZ:
+ m_op1 = gimple_call_arg (call, 0);
+ m_valid = true;
+ if (gimple_call_internal_p (call))
+ m_int = &op_cfn_clz_internal;
+ else
+ m_int = &op_cfn_clz;
+ break;
+
default:
break;
}
--
2.37.3