From fd53832b6e4a5424b03b6784b21a3718a41054d3 Mon Sep 17 00:00:00 2001
From: James Cherry <cherry@parallaxsw.com>
Date: Fri, 15 Dec 2023 17:19:19 -0700
Subject: [PATCH] TableAxis::findAxisIndex axis values are always ascending

Signed-off-by: James Cherry <cherry@parallaxsw.com>
---
 liberty/LibertyReader.cc | 23 +++++++++++++++++------
 liberty/TableModel.cc    | 28 +++++++++++++---------------
 parasitics/SpefReader.cc |  2 +-
 3 files changed, 31 insertions(+), 22 deletions(-)

diff --git a/liberty/LibertyReader.cc b/liberty/LibertyReader.cc
index f0b026aa..a5350d7a 100644
--- a/liberty/LibertyReader.cc
+++ b/liberty/LibertyReader.cc
@@ -1370,15 +1370,14 @@ LibertyReader::makeAxis(int index,
       float scale = tableVariableUnit(axis_var, units)->scale();
       scaleFloats(axis_values, scale);
     }
-    return std::make_shared<TableAxis>(axis_var, axis_values);
+    return make_shared<TableAxis>(axis_var, axis_values);
   }
   else if (axis_values) {
     libWarn(62, group, "missing variable_%d attribute.", index + 1);
     delete axis_values;
     axis_values_[index] = nullptr;
   }
-  // No warning for missing index_xx attributes because they are
-  // not required by ic_shell.
+  // No warning for missing index_xx attributes because they are not required.
   return nullptr;
 }
 
@@ -1448,8 +1447,20 @@ LibertyReader::visitIndex(int index,
       // Ignore index_xx in ecsm_waveform groups.
       && !stringEq(libertyGroup()->type(), "ecsm_waveform")) {
     FloatSeq *axis_values = readFloatSeq(attr, 1.0F);
-    if (axis_values)
+    if (axis_values) {
+      if (axis_values->empty())
+        libWarn(172, attr, "missing table index values.");
+      else {
+        float prev = (*axis_values)[0];
+        for (size_t i = 1; i < axis_values->size(); i++) {
+          float value = (*axis_values)[i];
+          if (value <= prev)
+            libWarn(173, attr, "non-increasing table index values.");
+          prev = value;
+        }
+      }
       axis_values_[index] = axis_values;
+    }
   }
 }
 
@@ -4366,7 +4377,7 @@ LibertyReader::makeTableAxis(int index)
     const Units *units = library_->units();
     float scale = tableVariableUnit(var, units)->scale();
     scaleFloats(values, scale);
-    axis_[index] = std::make_shared<TableAxis>(var, values);
+    axis_[index] = make_shared<TableAxis>(var, values);
   }
 }
 
@@ -5395,7 +5406,7 @@ RelatedPortGroup::setIsOneToOne(bool one)
 
 TimingGroup::TimingGroup(int line) :
   RelatedPortGroup(line),
-  attrs_(std::make_shared<TimingArcAttrs>()),
+  attrs_(make_shared<TimingArcAttrs>()),
   related_output_port_name_(nullptr),
   receiver_model_(nullptr)
 {
diff --git a/liberty/TableModel.cc b/liberty/TableModel.cc
index 4d7fe4df..43063b56 100644
--- a/liberty/TableModel.cc
+++ b/liberty/TableModel.cc
@@ -1413,7 +1413,7 @@ Table3::report(const Units *units,
       line = unit2->asString(axis2_->axisValue(axis_index2),digits);
       line += " |";
       for (size_t axis_index3 = 0; axis_index3 < axis3_->size(); axis_index3++) {
-        line += table_unit->asString(value(axis_index1, axis_index2, axis_index3), digits);
+        line += table_unit->asString(value(axis_index1, axis_index2, axis_index3),digits);
         line += " ";
       }
       report->reportLineString(line);
@@ -1448,19 +1448,18 @@ TableAxis::inBounds(float value) const
 size_t
 TableAxis::findAxisIndex(float value) const
 {
-  int max = static_cast<int>(values_->size()) - 1;
-  if (value <= (*values_)[0] || max == 0)
+  size_t size = values_->size();
+  if (size <= 1 || value <= (*values_)[0])
     return 0;
-  else if (value >= (*values_)[max])
-    // Return max-1 for value too large so interpolation pts are index,index+1.
-    return max - 1;
+  else if (value >= (*values_)[size - 1])
+    // Return max_index-1 for value too large so interpolation pts are index,index+1.
+    return size - 2;
   else {
     int lower = -1;
-    int upper = max + 1;
-    bool ascend = ((*values_)[max] >= (*values_)[0]);
+    int upper = size;
     while (upper - lower > 1) {
       int mid = (upper + lower) >> 1;
-      if ((value >= (*values_)[mid]) == ascend)
+      if (value >= (*values_)[mid])
 	lower = mid;
       else
 	upper = mid;
@@ -1475,13 +1474,12 @@ TableAxis::findAxisIndex(float value,
                          size_t &index,
                          bool &exists) const
 {
-  int max = static_cast<int>(values_->size()) - 1;
-  if (!values_->empty()
+  size_t size = values_->size();
+  if (size != 0
       && value >= (*values_)[0]
-      && value <= (*values_)[max]) {
+      && value <= (*values_)[size - 1]) {
     int lower = -1;
-    int upper = max + 1;
-    bool ascend = ((*values_)[max] >= (*values_)[0]);
+    int upper = size;
     while (upper - lower > 1) {
       int mid = (upper + lower) >> 1;
       if (value == (*values_)[mid]) {
@@ -1489,7 +1487,7 @@ TableAxis::findAxisIndex(float value,
         exists = true;
         return;
       }
-      if ((value > (*values_)[mid]) == ascend)
+      if (value > (*values_)[mid])
 	lower = mid;
       else
 	upper = mid;
diff --git a/parasitics/SpefReader.cc b/parasitics/SpefReader.cc
index 99e4bd57..cdff33a4 100644
--- a/parasitics/SpefReader.cc
+++ b/parasitics/SpefReader.cc
@@ -729,6 +729,6 @@ int
 SpefParse_error(const char *msg)
 {
   spefFlushBuffer();
-  sta::spef_reader->warn(179, "%s.", msg);
+  sta::spef_reader->warn(707, "%s.", msg);
   return 0;
 }