From be6755575685b2786637ba4815bcea768f234bbc Mon Sep 17 00:00:00 2001
From: Andrew Noyes <andrew@weaselab.dev>
Date: Thu, 1 Aug 2024 13:13:55 -0700
Subject: [PATCH] Simplify more "down left spine" loops

---
 ConflictSet.cpp | 31 ++++++++-----------------------
 1 file changed, 8 insertions(+), 23 deletions(-)

diff --git a/ConflictSet.cpp b/ConflictSet.cpp
index c947a2b..8734c02 100644
--- a/ConflictSet.cpp
+++ b/ConflictSet.cpp
@@ -2513,14 +2513,9 @@ bool checkRangeStartsWith(Node *n, std::span<const uint8_t> key, int begin,
   __builtin_unreachable(); // GCOVR_EXCL_LINE
 
 downLeftSpine:
-  for (;;) {
-    if (n->entryPresent) {
-      return n->entry.rangeVersion <= readVersion;
-    }
-    int c = getChildGeq(n, 0);
-    assert(c >= 0);
-    n = getChildExists(n, c);
+  for (; !n->entryPresent; n = getFirstChildExists(n)) {
   }
+  return n->entry.rangeVersion <= readVersion;
 }
 
 namespace {
@@ -2633,15 +2628,10 @@ template <bool kAVX512> struct CheckRangeLeftSide {
   }
 
   bool downLeftSpine() {
-    for (;;) {
-      if (n->entryPresent) {
-        ok = n->entry.rangeVersion <= readVersion;
-        return true;
-      }
-      int c = getChildGeq(n, 0);
-      assert(c >= 0);
-      n = getChildExists(n, c);
+    for (; !n->entryPresent; n = getFirstChildExists(n)) {
     }
+    ok = n->entry.rangeVersion <= readVersion;
+    return true;
   }
 };
 
@@ -2770,15 +2760,10 @@ template <bool kAVX512> struct CheckRangeRightSide {
   }
 
   bool downLeftSpine() {
-    for (;;) {
-      if (n->entryPresent) {
-        ok = n->entry.rangeVersion <= readVersion;
-        return true;
-      }
-      int c = getChildGeq(n, 0);
-      assert(c >= 0);
-      n = getChildExists(n, c);
+    for (; !n->entryPresent; n = getFirstChildExists(n)) {
     }
+    ok = n->entry.rangeVersion <= readVersion;
+    return true;
   }
 };
 } // namespace