Simplify StackBounds.

Source/wtf/StackStats.cpp

Index: Source/wtf/StackStats.cpp
diff --git a/Source/wtf/StackStats.cpp b/Source/wtf/StackStats.cpp
index 824bf466a2e5d47b88c3f94e880f36691de7b454..3df0c220085f86c3d0688cc39faacf75ad5f8e8d 100644
--- a/Source/wtf/StackStats.cpp
+++ b/Source/wtf/StackStats.cpp
@@ -81,7 +81,6 @@ StackStats::CheckPoint::CheckPoint()
     StackStats::PerThreadStats& t = threadData->stackStats();
     const StackBounds& stack = threadData->stack();
 
-    bool isGrowingDownward = stack.isGrowingDownward();
     bool needToLog = false;
     char* current = reinterpret_cast<char*>(this);
     char* last = reinterpret_cast<char*>(t.m_currentCheckPoint);
@@ -99,8 +98,6 @@ StackStats::CheckPoint::CheckPoint()
 
     // Update the stack height stats:
     int height = t.m_stackStart - current;
-    if (!isGrowingDownward)
-        height = -height;
     if (height > StackStats::s_maxStackHeight) {
         StackStats::s_maxStackHeight = height;
         needToLog = true;
@@ -108,8 +105,6 @@ StackStats::CheckPoint::CheckPoint()
 
     // Update the checkpoint diff stats:
     int diff = last - current;
-    if (!isGrowingDownward)
-        diff = -diff;
     if (diff > StackStats::s_maxCheckPointDiff) {
         StackStats::s_maxCheckPointDiff = diff;
         needToLog = true;
@@ -146,14 +141,10 @@ StackStats::CheckPoint::~CheckPoint()
 #if ENABLE(VERBOSE_STACK_STATS)
     if (!m_prev) {
         const StackBounds& stack = threadData->stack();
-        bool isGrowingDownward = stack.isGrowingDownward();
 
         char* current = reinterpret_cast<char*>(this);
         int height = t.m_stackStart - current;
 
-        if (!isGrowingDownward)
-            height = -height;
-
         dataLogF(" POP to %p diff max %.1fk | reentry %d/%d max | height %.1fk/max %.1fk | stack %p size %.1fk)\n",
             this, StackStats::s_maxCheckPointDiff / 1024.0,
             t.m_reentryDepth, StackStats::s_maxReentryDepth,
@@ -170,8 +161,6 @@ void StackStats::probe()
     StackStats::PerThreadStats& t = threadData->stackStats();
     const StackBounds& stack = threadData->stack();
 
-    bool isGrowingDownward = stack.isGrowingDownward();
-
     bool needToLog = false;
 
     int dummy;
@@ -187,8 +176,6 @@ void StackStats::probe()
 
     // Update the stack height stats:
     int height = t.m_stackStart - current;
-    if (!isGrowingDownward)
-        height = -height;
     if (height > StackStats::s_maxStackHeight) {
         StackStats::s_maxStackHeight = height;
         needToLog = true;
@@ -196,8 +183,6 @@ void StackStats::probe()
 
     // Update the checkpoint diff stats:
     int diff = last - current;
-    if (!isGrowingDownward)
-        diff = -diff;
     if (diff > StackStats::s_maxCheckPointDiff) {
         StackStats::s_maxCheckPointDiff = diff;
         needToLog = true;
@@ -231,8 +216,6 @@ StackStats::LayoutCheckPoint::LayoutCheckPoint()
     StackStats::PerThreadStats& t = threadData->stackStats();
     const StackBounds& stack = threadData->stack();
 
-    bool isGrowingDownward = stack.isGrowingDownward();
-
     // Push this checkpoint:
     m_prev = StackStats::s_topLayoutCheckPoint;
     if (m_prev)
@@ -258,24 +241,18 @@ StackStats::LayoutCheckPoint::LayoutCheckPoint()
 
     // Update the stack height stats:
     int height = t.m_stackStart - current;
-    if (!isGrowingDownward)
-        height = -height;
     if (height > StackStats::s_maxStackHeight) {
         StackStats::s_maxStackHeight = height;
         needToLog = true;
     }
 
     // Update the layout checkpoint diff stats:
-    if (!isGrowingDownward)
-        diff = -diff;
     if (diff > StackStats::s_maxLayoutCheckPointDiff) {
         StackStats::s_maxLayoutCheckPointDiff = diff;
         needToLog = true;
     }
 
     // Update the total layout checkpoint diff stats:
-    if (!isGrowingDownward)
-        totalDiff = -totalDiff;
     if (totalDiff > StackStats::s_maxTotalLayoutCheckPointDiff) {
         StackStats::s_maxTotalLayoutCheckPointDiff = totalDiff;
         needToLog = true;