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From: Tamar Christina <tamar.christina@arm.com>
To: gcc-patches@gcc.gnu.org
Cc: nd@arm.com, amacleod@redhat.com, aldyh@redhat.com
Subject: [PATCH 2/4][ranger]: Add range-ops for widen addition and widen multiplication [PR108583]
Date: Mon, 27 Feb 2023 12:33:18 +0000	[thread overview]
Message-ID: <Y/yjDtzup8FaUIZF@arm.com> (raw)
In-Reply-To: <patch-16928-tamar@arm.com>

[-- Attachment #1: Type: text/plain, Size: 8976 bytes --]

Hi All,

This adds range-ops for widening addition and widening multiplication.

I couldn't figure out how to write a test for this.  It looks like there are
self tests but not a way to write standalone ones?  I did create testcases in
the patch 3/4 which tests the end result.

Bootstrapped Regtested on aarch64-none-linux-gnu and no issues.

Ok for master?

Thanks,
Tamar

gcc/ChangeLog:

	PR target/108583
	* gimple-range-op.h (gimple_range_op_handler): Add maybe_non_standard.
	* gimple-range-op.cc (gimple_range_op_handler::gimple_range_op_handler):
	Use it.
	(gimple_range_op_handler::maybe_non_standard): New.
	* range-op.cc (class operator_widen_plus_signed,
	operator_widen_plus_signed::wi_fold, class operator_widen_plus_unsigned,
	operator_widen_plus_unsigned::wi_fold, class operator_widen_mult_signed,
	operator_widen_mult_signed::wi_fold, class operator_widen_mult_unsigned,
	operator_widen_mult_unsigned::wi_fold,
	ptr_op_widen_mult_signed, ptr_op_widen_mult_unsigned,
	ptr_op_widen_plus_signed, ptr_op_widen_plus_unsigned): New.
	* range-op.h (ptr_op_widen_mult_signed, ptr_op_widen_mult_unsigned,
	ptr_op_widen_plus_signed, ptr_op_widen_plus_unsigned): New

Co-Authored-By: Andrew MacLeod <amacleod@redhat.com>

--- inline copy of patch -- 
diff --git a/gcc/gimple-range-op.h b/gcc/gimple-range-op.h
index 743b858126e333ea9590c0f175aacb476260c048..1bf63c5ce6f5db924a1f5907ab4539e376281bd0 100644
--- a/gcc/gimple-range-op.h
+++ b/gcc/gimple-range-op.h
@@ -41,6 +41,7 @@ public:
 		 relation_trio = TRIO_VARYING);
 private:
   void maybe_builtin_call ();
+  void maybe_non_standard ();
   gimple *m_stmt;
   tree m_op1, m_op2;
 };
diff --git a/gcc/gimple-range-op.cc b/gcc/gimple-range-op.cc
index d9dfdc56939bb62ade72726b15c3d5e87e4ddcd1..ad13c873c6303db5b68b74db1562c0db6763101f 100644
--- a/gcc/gimple-range-op.cc
+++ b/gcc/gimple-range-op.cc
@@ -179,6 +179,8 @@ gimple_range_op_handler::gimple_range_op_handler (gimple *s)
   // statements.
   if (is_a <gcall *> (m_stmt))
     maybe_builtin_call ();
+  else
+    maybe_non_standard ();
 }
 
 // Calculate what we can determine of the range of this unary
@@ -764,6 +766,44 @@ public:
   }
 } op_cfn_parity;
 
+// Set up a gimple_range_op_handler for any nonstandard function which can be
+// supported via range-ops.
+
+void
+gimple_range_op_handler::maybe_non_standard ()
+{
+  range_operator *signed_op = ptr_op_widen_mult_signed;
+  range_operator *unsigned_op = ptr_op_widen_mult_unsigned;
+  if (gimple_code (m_stmt) == GIMPLE_ASSIGN)
+    switch (gimple_assign_rhs_code (m_stmt))
+      {
+	case WIDEN_PLUS_EXPR:
+	{
+	  signed_op = ptr_op_widen_plus_signed;
+	  unsigned_op = ptr_op_widen_plus_unsigned;
+	}
+	gcc_fallthrough ();
+	case WIDEN_MULT_EXPR:
+	{
+	  m_valid = true;
+	  m_op1 = gimple_assign_rhs1 (m_stmt);
+	  m_op2 = gimple_assign_rhs2 (m_stmt);
+	  bool signed1 = TYPE_SIGN (TREE_TYPE (m_op1)) == SIGNED;
+	  bool signed2 = TYPE_SIGN (TREE_TYPE (m_op2)) == SIGNED;
+	  if (signed2 && !signed1)
+	    std::swap (m_op1, m_op2);
+
+	  if (signed1 || signed2)
+	    m_int = signed_op;
+	  else
+	    m_int = unsigned_op;
+	  break;
+	}
+	default:
+	  break;
+      }
+}
+
 // Set up a gimple_range_op_handler for any built in function which can be
 // supported via range-ops.
 
diff --git a/gcc/range-op.h b/gcc/range-op.h
index f00b747f08a1fa8404c63bfe5a931b4048008b03..b1eeac70df81f2bdf228af7adff5399e7ac5e5d6 100644
--- a/gcc/range-op.h
+++ b/gcc/range-op.h
@@ -311,4 +311,8 @@ private:
 // This holds the range op table for floating point operations.
 extern floating_op_table *floating_tree_table;
 
+extern range_operator *ptr_op_widen_mult_signed;
+extern range_operator *ptr_op_widen_mult_unsigned;
+extern range_operator *ptr_op_widen_plus_signed;
+extern range_operator *ptr_op_widen_plus_unsigned;
 #endif // GCC_RANGE_OP_H
diff --git a/gcc/range-op.cc b/gcc/range-op.cc
index 5c67bce6d3aab81ad3186b902e09d6a96878d9bb..718ccb6f074e1a2a9ef1b7a5d4e879898d4a7fc3 100644
--- a/gcc/range-op.cc
+++ b/gcc/range-op.cc
@@ -1556,6 +1556,73 @@ operator_plus::op2_range (irange &r, tree type,
   return op1_range (r, type, lhs, op1, rel.swap_op1_op2 ());
 }
 
+class operator_widen_plus_signed : public range_operator
+{
+public:
+  virtual void wi_fold (irange &r, tree type,
+			const wide_int &lh_lb,
+			const wide_int &lh_ub,
+			const wide_int &rh_lb,
+			const wide_int &rh_ub) const;
+} op_widen_plus_signed;
+range_operator *ptr_op_widen_plus_signed = &op_widen_plus_signed;
+
+void
+operator_widen_plus_signed::wi_fold (irange &r, tree type,
+				     const wide_int &lh_lb,
+				     const wide_int &lh_ub,
+				     const wide_int &rh_lb,
+				     const wide_int &rh_ub) const
+{
+   wi::overflow_type ov_lb, ov_ub;
+   signop s = TYPE_SIGN (type);
+
+   wide_int lh_wlb
+     = wide_int::from (lh_lb, wi::get_precision (lh_lb) * 2, SIGNED);
+   wide_int lh_wub
+     = wide_int::from (lh_ub, wi::get_precision (lh_ub) * 2, SIGNED);
+   wide_int rh_wlb = wide_int::from (rh_lb, wi::get_precision (rh_lb) * 2, s);
+   wide_int rh_wub = wide_int::from (rh_ub, wi::get_precision (rh_ub) * 2, s);
+
+   wide_int new_lb = wi::add (lh_wlb, rh_wlb, s, &ov_lb);
+   wide_int new_ub = wi::add (lh_wub, rh_wub, s, &ov_ub);
+
+   r = int_range<2> (type, new_lb, new_ub);
+}
+
+class operator_widen_plus_unsigned : public range_operator
+{
+public:
+  virtual void wi_fold (irange &r, tree type,
+			const wide_int &lh_lb,
+			const wide_int &lh_ub,
+			const wide_int &rh_lb,
+			const wide_int &rh_ub) const;
+} op_widen_plus_unsigned;
+range_operator *ptr_op_widen_plus_unsigned = &op_widen_plus_unsigned;
+
+void
+operator_widen_plus_unsigned::wi_fold (irange &r, tree type,
+				       const wide_int &lh_lb,
+				       const wide_int &lh_ub,
+				       const wide_int &rh_lb,
+				       const wide_int &rh_ub) const
+{
+   wi::overflow_type ov_lb, ov_ub;
+   signop s = TYPE_SIGN (type);
+
+   wide_int lh_wlb
+     = wide_int::from (lh_lb, wi::get_precision (lh_lb) * 2, UNSIGNED);
+   wide_int lh_wub
+     = wide_int::from (lh_ub, wi::get_precision (lh_ub) * 2, UNSIGNED);
+   wide_int rh_wlb = wide_int::from (rh_lb, wi::get_precision (rh_lb) * 2, s);
+   wide_int rh_wub = wide_int::from (rh_ub, wi::get_precision (rh_ub) * 2, s);
+
+   wide_int new_lb = wi::add (lh_wlb, rh_wlb, s, &ov_lb);
+   wide_int new_ub = wi::add (lh_wub, rh_wub, s, &ov_ub);
+
+   r = int_range<2> (type, new_lb, new_ub);
+}
 
 class operator_minus : public range_operator
 {
@@ -2031,6 +2098,70 @@ operator_mult::wi_fold (irange &r, tree type,
     }
 }
 
+class operator_widen_mult_signed : public range_operator
+{
+public:
+  virtual void wi_fold (irange &r, tree type,
+			const wide_int &lh_lb,
+			const wide_int &lh_ub,
+			const wide_int &rh_lb,
+			const wide_int &rh_ub)
+    const;
+} op_widen_mult_signed;
+range_operator *ptr_op_widen_mult_signed = &op_widen_mult_signed;
+
+void
+operator_widen_mult_signed::wi_fold (irange &r, tree type,
+				     const wide_int &lh_lb,
+				     const wide_int &lh_ub,
+				     const wide_int &rh_lb,
+				     const wide_int &rh_ub) const
+{
+  signop s = TYPE_SIGN (type);
+
+  wide_int lh_wlb = wide_int::from (lh_lb, wi::get_precision (lh_lb) * 2, SIGNED);
+  wide_int lh_wub = wide_int::from (lh_ub, wi::get_precision (lh_ub) * 2, SIGNED);
+  wide_int rh_wlb = wide_int::from (rh_lb, wi::get_precision (rh_lb) * 2, s);
+  wide_int rh_wub = wide_int::from (rh_ub, wi::get_precision (rh_ub) * 2, s);
+
+  /* We don't expect a widening multiplication to be able to overflow but range
+     calculations for multiplications are complicated.  After widening the
+     operands lets call the base class.  */
+  return op_mult.wi_fold (r, type, lh_wlb, lh_wub, rh_wlb, rh_wub);
+}
+
+
+class operator_widen_mult_unsigned : public range_operator
+{
+public:
+  virtual void wi_fold (irange &r, tree type,
+			const wide_int &lh_lb,
+			const wide_int &lh_ub,
+			const wide_int &rh_lb,
+			const wide_int &rh_ub)
+    const;
+} op_widen_mult_unsigned;
+range_operator *ptr_op_widen_mult_unsigned = &op_widen_mult_unsigned;
+
+void
+operator_widen_mult_unsigned::wi_fold (irange &r, tree type,
+				       const wide_int &lh_lb,
+				       const wide_int &lh_ub,
+				       const wide_int &rh_lb,
+				       const wide_int &rh_ub) const
+{
+  signop s = TYPE_SIGN (type);
+
+  wide_int lh_wlb = wide_int::from (lh_lb, wi::get_precision (lh_lb) * 2, UNSIGNED);
+  wide_int lh_wub = wide_int::from (lh_ub, wi::get_precision (lh_ub) * 2, UNSIGNED);
+  wide_int rh_wlb = wide_int::from (rh_lb, wi::get_precision (rh_lb) * 2, s);
+  wide_int rh_wub = wide_int::from (rh_ub, wi::get_precision (rh_ub) * 2, s);
+
+  /* We don't expect a widening multiplication to be able to overflow but range
+     calculations for multiplications are complicated.  After widening the
+     operands lets call the base class.  */
+  return op_mult.wi_fold (r, type, lh_wlb, lh_wub, rh_wlb, rh_wub);
+}
 
 class operator_div : public cross_product_operator
 {




-- 

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diff --git a/gcc/gimple-range-op.h b/gcc/gimple-range-op.h
index 743b858126e333ea9590c0f175aacb476260c048..1bf63c5ce6f5db924a1f5907ab4539e376281bd0 100644
--- a/gcc/gimple-range-op.h
+++ b/gcc/gimple-range-op.h
@@ -41,6 +41,7 @@ public:
 		 relation_trio = TRIO_VARYING);
 private:
   void maybe_builtin_call ();
+  void maybe_non_standard ();
   gimple *m_stmt;
   tree m_op1, m_op2;
 };
diff --git a/gcc/gimple-range-op.cc b/gcc/gimple-range-op.cc
index d9dfdc56939bb62ade72726b15c3d5e87e4ddcd1..ad13c873c6303db5b68b74db1562c0db6763101f 100644
--- a/gcc/gimple-range-op.cc
+++ b/gcc/gimple-range-op.cc
@@ -179,6 +179,8 @@ gimple_range_op_handler::gimple_range_op_handler (gimple *s)
   // statements.
   if (is_a <gcall *> (m_stmt))
     maybe_builtin_call ();
+  else
+    maybe_non_standard ();
 }
 
 // Calculate what we can determine of the range of this unary
@@ -764,6 +766,44 @@ public:
   }
 } op_cfn_parity;
 
+// Set up a gimple_range_op_handler for any nonstandard function which can be
+// supported via range-ops.
+
+void
+gimple_range_op_handler::maybe_non_standard ()
+{
+  range_operator *signed_op = ptr_op_widen_mult_signed;
+  range_operator *unsigned_op = ptr_op_widen_mult_unsigned;
+  if (gimple_code (m_stmt) == GIMPLE_ASSIGN)
+    switch (gimple_assign_rhs_code (m_stmt))
+      {
+	case WIDEN_PLUS_EXPR:
+	{
+	  signed_op = ptr_op_widen_plus_signed;
+	  unsigned_op = ptr_op_widen_plus_unsigned;
+	}
+	gcc_fallthrough ();
+	case WIDEN_MULT_EXPR:
+	{
+	  m_valid = true;
+	  m_op1 = gimple_assign_rhs1 (m_stmt);
+	  m_op2 = gimple_assign_rhs2 (m_stmt);
+	  bool signed1 = TYPE_SIGN (TREE_TYPE (m_op1)) == SIGNED;
+	  bool signed2 = TYPE_SIGN (TREE_TYPE (m_op2)) == SIGNED;
+	  if (signed2 && !signed1)
+	    std::swap (m_op1, m_op2);
+
+	  if (signed1 || signed2)
+	    m_int = signed_op;
+	  else
+	    m_int = unsigned_op;
+	  break;
+	}
+	default:
+	  break;
+      }
+}
+
 // Set up a gimple_range_op_handler for any built in function which can be
 // supported via range-ops.
 
diff --git a/gcc/range-op.h b/gcc/range-op.h
index f00b747f08a1fa8404c63bfe5a931b4048008b03..b1eeac70df81f2bdf228af7adff5399e7ac5e5d6 100644
--- a/gcc/range-op.h
+++ b/gcc/range-op.h
@@ -311,4 +311,8 @@ private:
 // This holds the range op table for floating point operations.
 extern floating_op_table *floating_tree_table;
 
+extern range_operator *ptr_op_widen_mult_signed;
+extern range_operator *ptr_op_widen_mult_unsigned;
+extern range_operator *ptr_op_widen_plus_signed;
+extern range_operator *ptr_op_widen_plus_unsigned;
 #endif // GCC_RANGE_OP_H
diff --git a/gcc/range-op.cc b/gcc/range-op.cc
index 5c67bce6d3aab81ad3186b902e09d6a96878d9bb..718ccb6f074e1a2a9ef1b7a5d4e879898d4a7fc3 100644
--- a/gcc/range-op.cc
+++ b/gcc/range-op.cc
@@ -1556,6 +1556,73 @@ operator_plus::op2_range (irange &r, tree type,
   return op1_range (r, type, lhs, op1, rel.swap_op1_op2 ());
 }
 
+class operator_widen_plus_signed : public range_operator
+{
+public:
+  virtual void wi_fold (irange &r, tree type,
+			const wide_int &lh_lb,
+			const wide_int &lh_ub,
+			const wide_int &rh_lb,
+			const wide_int &rh_ub) const;
+} op_widen_plus_signed;
+range_operator *ptr_op_widen_plus_signed = &op_widen_plus_signed;
+
+void
+operator_widen_plus_signed::wi_fold (irange &r, tree type,
+				     const wide_int &lh_lb,
+				     const wide_int &lh_ub,
+				     const wide_int &rh_lb,
+				     const wide_int &rh_ub) const
+{
+   wi::overflow_type ov_lb, ov_ub;
+   signop s = TYPE_SIGN (type);
+
+   wide_int lh_wlb
+     = wide_int::from (lh_lb, wi::get_precision (lh_lb) * 2, SIGNED);
+   wide_int lh_wub
+     = wide_int::from (lh_ub, wi::get_precision (lh_ub) * 2, SIGNED);
+   wide_int rh_wlb = wide_int::from (rh_lb, wi::get_precision (rh_lb) * 2, s);
+   wide_int rh_wub = wide_int::from (rh_ub, wi::get_precision (rh_ub) * 2, s);
+
+   wide_int new_lb = wi::add (lh_wlb, rh_wlb, s, &ov_lb);
+   wide_int new_ub = wi::add (lh_wub, rh_wub, s, &ov_ub);
+
+   r = int_range<2> (type, new_lb, new_ub);
+}
+
+class operator_widen_plus_unsigned : public range_operator
+{
+public:
+  virtual void wi_fold (irange &r, tree type,
+			const wide_int &lh_lb,
+			const wide_int &lh_ub,
+			const wide_int &rh_lb,
+			const wide_int &rh_ub) const;
+} op_widen_plus_unsigned;
+range_operator *ptr_op_widen_plus_unsigned = &op_widen_plus_unsigned;
+
+void
+operator_widen_plus_unsigned::wi_fold (irange &r, tree type,
+				       const wide_int &lh_lb,
+				       const wide_int &lh_ub,
+				       const wide_int &rh_lb,
+				       const wide_int &rh_ub) const
+{
+   wi::overflow_type ov_lb, ov_ub;
+   signop s = TYPE_SIGN (type);
+
+   wide_int lh_wlb
+     = wide_int::from (lh_lb, wi::get_precision (lh_lb) * 2, UNSIGNED);
+   wide_int lh_wub
+     = wide_int::from (lh_ub, wi::get_precision (lh_ub) * 2, UNSIGNED);
+   wide_int rh_wlb = wide_int::from (rh_lb, wi::get_precision (rh_lb) * 2, s);
+   wide_int rh_wub = wide_int::from (rh_ub, wi::get_precision (rh_ub) * 2, s);
+
+   wide_int new_lb = wi::add (lh_wlb, rh_wlb, s, &ov_lb);
+   wide_int new_ub = wi::add (lh_wub, rh_wub, s, &ov_ub);
+
+   r = int_range<2> (type, new_lb, new_ub);
+}
 
 class operator_minus : public range_operator
 {
@@ -2031,6 +2098,70 @@ operator_mult::wi_fold (irange &r, tree type,
     }
 }
 
+class operator_widen_mult_signed : public range_operator
+{
+public:
+  virtual void wi_fold (irange &r, tree type,
+			const wide_int &lh_lb,
+			const wide_int &lh_ub,
+			const wide_int &rh_lb,
+			const wide_int &rh_ub)
+    const;
+} op_widen_mult_signed;
+range_operator *ptr_op_widen_mult_signed = &op_widen_mult_signed;
+
+void
+operator_widen_mult_signed::wi_fold (irange &r, tree type,
+				     const wide_int &lh_lb,
+				     const wide_int &lh_ub,
+				     const wide_int &rh_lb,
+				     const wide_int &rh_ub) const
+{
+  signop s = TYPE_SIGN (type);
+
+  wide_int lh_wlb = wide_int::from (lh_lb, wi::get_precision (lh_lb) * 2, SIGNED);
+  wide_int lh_wub = wide_int::from (lh_ub, wi::get_precision (lh_ub) * 2, SIGNED);
+  wide_int rh_wlb = wide_int::from (rh_lb, wi::get_precision (rh_lb) * 2, s);
+  wide_int rh_wub = wide_int::from (rh_ub, wi::get_precision (rh_ub) * 2, s);
+
+  /* We don't expect a widening multiplication to be able to overflow but range
+     calculations for multiplications are complicated.  After widening the
+     operands lets call the base class.  */
+  return op_mult.wi_fold (r, type, lh_wlb, lh_wub, rh_wlb, rh_wub);
+}
+
+
+class operator_widen_mult_unsigned : public range_operator
+{
+public:
+  virtual void wi_fold (irange &r, tree type,
+			const wide_int &lh_lb,
+			const wide_int &lh_ub,
+			const wide_int &rh_lb,
+			const wide_int &rh_ub)
+    const;
+} op_widen_mult_unsigned;
+range_operator *ptr_op_widen_mult_unsigned = &op_widen_mult_unsigned;
+
+void
+operator_widen_mult_unsigned::wi_fold (irange &r, tree type,
+				       const wide_int &lh_lb,
+				       const wide_int &lh_ub,
+				       const wide_int &rh_lb,
+				       const wide_int &rh_ub) const
+{
+  signop s = TYPE_SIGN (type);
+
+  wide_int lh_wlb = wide_int::from (lh_lb, wi::get_precision (lh_lb) * 2, UNSIGNED);
+  wide_int lh_wub = wide_int::from (lh_ub, wi::get_precision (lh_ub) * 2, UNSIGNED);
+  wide_int rh_wlb = wide_int::from (rh_lb, wi::get_precision (rh_lb) * 2, s);
+  wide_int rh_wub = wide_int::from (rh_ub, wi::get_precision (rh_ub) * 2, s);
+
+  /* We don't expect a widening multiplication to be able to overflow but range
+     calculations for multiplications are complicated.  After widening the
+     operands lets call the base class.  */
+  return op_mult.wi_fold (r, type, lh_wlb, lh_wub, rh_wlb, rh_wub);
+}
 
 class operator_div : public cross_product_operator
 {




  reply	other threads:[~2023-02-27 12:33 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-02-27 12:32 [PATCH 1/4]middle-end: Revert can_special_div_by_const changes [PR108583] Tamar Christina
2023-02-27 12:33 ` Tamar Christina [this message]
2023-03-06 11:20   ` [PATCH 2/4][ranger]: Add range-ops for widen addition and widen multiplication [PR108583] Tamar Christina
2023-03-08  8:57     ` Aldy Hernandez
2023-03-09 19:37       ` Tamar Christina
2023-03-10 13:32         ` Andrew MacLeod
2023-03-10 14:11           ` Tamar Christina
2023-03-10 14:30             ` Richard Biener
2023-02-27 12:33 ` [PATCH 3/4]middle-end: Implement preferred_div_as_shifts_over_mult [PR108583] Tamar Christina
2023-03-06 11:23   ` Tamar Christina
2023-03-08  8:55     ` Richard Sandiford
2023-03-09 19:39       ` Tamar Christina
2023-03-10  8:39         ` Richard Sandiford
2023-02-27 12:34 ` [PATCH 4/4]AArch64 Update div-bitmask to implement new optab instead of target hook [PR108583] Tamar Christina
2023-03-06 11:21   ` Tamar Christina
2023-03-08  9:17     ` Richard Sandiford
2023-03-08  9:25       ` Tamar Christina
2023-03-08 10:44         ` Richard Sandiford
2023-02-27 14:07 ` [PATCH 1/4]middle-end: Revert can_special_div_by_const changes [PR108583] Richard Biener

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