[APInt] Add unsigned overloads of shift functions

Add overloads of sshl_ov, ushl_ov, sshl_sat and ushl_sat that take the shift amount as unsigned instead of APInt. This matches what we do for the normal shift operators and can help to avoid creating temporary APInts in some cases. Differential Revision: https://reviews.llvm.org/D151420
llvm · May 25, 2023 · bf358e2 · bf358e2
1 parent 298843c
commit bf358e2
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Showing 2 changed files with 25 additions and 5 deletions.
diff --git a/llvm/include/llvm/ADT/APInt.h b/llvm/include/llvm/ADT/APInt.h
@@ -1003,7 +1003,9 @@ class [[nodiscard]] APInt {
   APInt smul_ov(const APInt &RHS, bool &Overflow) const;
   APInt umul_ov(const APInt &RHS, bool &Overflow) const;
   APInt sshl_ov(const APInt &Amt, bool &Overflow) const;
+  APInt sshl_ov(unsigned Amt, bool &Overflow) const;
   APInt ushl_ov(const APInt &Amt, bool &Overflow) const;
+  APInt ushl_ov(unsigned Amt, bool &Overflow) const;
 
   // Operations that saturate
   APInt sadd_sat(const APInt &RHS) const;
@@ -1013,7 +1015,9 @@ class [[nodiscard]] APInt {
   APInt smul_sat(const APInt &RHS) const;
   APInt umul_sat(const APInt &RHS) const;
   APInt sshl_sat(const APInt &RHS) const;
+  APInt sshl_sat(unsigned RHS) const;
   APInt ushl_sat(const APInt &RHS) const;
+  APInt ushl_sat(unsigned RHS) const;
 
   /// Array-indexing support.
   ///

diff --git a/llvm/lib/Support/APInt.cpp b/llvm/lib/Support/APInt.cpp
@@ -1984,24 +1984,32 @@ APInt APInt::umul_ov(const APInt &RHS, bool &Overflow) const {
 }
 
 APInt APInt::sshl_ov(const APInt &ShAmt, bool &Overflow) const {
-  Overflow = ShAmt.uge(getBitWidth());
+  return sshl_ov(ShAmt.getLimitedValue(getBitWidth()), Overflow);
+}
+
+APInt APInt::sshl_ov(unsigned ShAmt, bool &Overflow) const {
+  Overflow = ShAmt >= getBitWidth();
   if (Overflow)
     return APInt(BitWidth, 0);
 
   if (isNonNegative()) // Don't allow sign change.
-    Overflow = ShAmt.uge(countl_zero());
+    Overflow = ShAmt >= countl_zero();
   else
-    Overflow = ShAmt.uge(countl_one());
+    Overflow = ShAmt >= countl_one();
 
   return *this << ShAmt;
 }
 
 APInt APInt::ushl_ov(const APInt &ShAmt, bool &Overflow) const {
-  Overflow = ShAmt.uge(getBitWidth());
+  return ushl_ov(ShAmt.getLimitedValue(getBitWidth()), Overflow);
+}
+
+APInt APInt::ushl_ov(unsigned ShAmt, bool &Overflow) const {
+  Overflow = ShAmt >= getBitWidth();
   if (Overflow)
     return APInt(BitWidth, 0);
 
-  Overflow = ShAmt.ugt(countl_zero());
+  Overflow = ShAmt > countl_zero();
 
   return *this << ShAmt;
 }
@@ -2067,6 +2075,10 @@ APInt APInt::umul_sat(const APInt &RHS) const {
 }
 
 APInt APInt::sshl_sat(const APInt &RHS) const {
+  return sshl_sat(RHS.getLimitedValue(getBitWidth()));
+}
+
+APInt APInt::sshl_sat(unsigned RHS) const {
   bool Overflow;
   APInt Res = sshl_ov(RHS, Overflow);
   if (!Overflow)
@@ -2077,6 +2089,10 @@ APInt APInt::sshl_sat(const APInt &RHS) const {
 }
 
 APInt APInt::ushl_sat(const APInt &RHS) const {
+  return ushl_sat(RHS.getLimitedValue(getBitWidth()));
+}
+
+APInt APInt::ushl_sat(unsigned RHS) const {
   bool Overflow;
   APInt Res = ushl_ov(RHS, Overflow);
   if (!Overflow)