[ADT] Simplify SparseBitVectorElement::unionWith and friends. NFC.

[jayfoad]

No description provided.

[llvmbot]

@llvm/pr-subscribers-llvm-adt

Author: Jay Foad (jayfoad)

Changes

---

Full diff: https://github.com/llvm/llvm-project/pull/143775.diff

1 Files Affected:

• (modified) llvm/include/llvm/ADT/SparseBitVector.h (+6-6)

diff --git a/llvm/include/llvm/ADT/SparseBitVector.h b/llvm/include/llvm/ADT/SparseBitVector.h
index 7151af6146e6e..1e6f8b22ca997 100644
--- a/llvm/include/llvm/ADT/SparseBitVector.h
+++ b/llvm/include/llvm/ADT/SparseBitVector.h
@@ -172,10 +172,10 @@ template <unsigned ElementSize = 128> struct SparseBitVectorElement {
   bool unionWith(const SparseBitVectorElement &RHS) {
     bool changed = false;
     for (unsigned i = 0; i < BITWORDS_PER_ELEMENT; ++i) {
-      BitWord old = changed ? 0 : Bits[i];
+      BitWord old = Bits[i];
 
       Bits[i] |= RHS.Bits[i];
-      if (!changed && old != Bits[i])
+      if (old != Bits[i])
         changed = true;
     }
     return changed;
@@ -199,13 +199,13 @@ template <unsigned ElementSize = 128> struct SparseBitVectorElement {
 
     BecameZero = false;
     for (unsigned i = 0; i < BITWORDS_PER_ELEMENT; ++i) {
-      BitWord old = changed ? 0 : Bits[i];
+      BitWord old = Bits[i];
 
       Bits[i] &= RHS.Bits[i];
       if (Bits[i] != 0)
         allzero = false;
 
-      if (!changed && old != Bits[i])
+      if (old != Bits[i])
         changed = true;
     }
     BecameZero = allzero;
@@ -222,13 +222,13 @@ template <unsigned ElementSize = 128> struct SparseBitVectorElement {
 
     BecameZero = false;
     for (unsigned i = 0; i < BITWORDS_PER_ELEMENT; ++i) {
-      BitWord old = changed ? 0 : Bits[i];
+      BitWord old = Bits[i];
 
       Bits[i] &= ~RHS.Bits[i];
       if (Bits[i] != 0)
         allzero = false;
 
-      if (!changed && old != Bits[i])
+      if (old != Bits[i])
         changed = true;
     }
     BecameZero = allzero;

[jayfoad]

No effect on compile time: https://llvm-compile-time-tracker.com/compare.php?from=756e7cfd86c7f2bf20aaa1a3f87b5aa72ec128b4&to=1775d80ec58eeeac8be33498d3ee860ded281e36&stat=instructions:u