cleanup structure packing calculation

1 files changed, 7 insertions, 4 deletions

diff --git a/src/analyzer.js b/src/analyzer.js
index 15e7b291..e7f0dfff 100644
--- a/src/analyzer.js
+++ b/src/analyzer.js
@@ -182,15 +182,20 @@ function analyzer(data) {
             more = true;
             return;
           }
+          // Calculate aligned size, just like C structs should be. TODO: Consider
+          // requesting that compilation be done with #pragma pack(push) /n #pragma pack(1),
+          // which would remove much of the complexity here.
           type.flatSize = 0;
           var diffs = [];
-          var prev = -1;
+          var prev = -1, maxSize = -1;
           type.flatIndexes = type.fields.map(function(field) {
             var size;
             if (isNumberType(field) || isPointerType(field)) {
               size = getNativeFieldSize(field, true); // pack char; char; in structs, also char[X]s.
+              maxSize = Math.max(maxSize, size);
             } else if (isStructType(field)) {
               size = item.types[field].flatSize;
+              maxSize = Math.max(maxSize, QUANTUM_SIZE);
             } else {
               dprint('Unclear type in struct: ' + field + ', in ' + type.name_);
               assert(0);
@@ -203,14 +208,12 @@ function analyzer(data) {
             prev = curr;
             return curr;
           });
+          type.flatSize = Runtime.alignMemory(type.flatSize, maxSize);
           if (diffs.length == 0) {
             type.flatFactor = type.flatSize;
           } else if (dedup(diffs).length == 1) {
             type.flatFactor = diffs[0];
           }
-          if (type.flatSize > QUANTUM_SIZE) {
-            type.flatSize = Runtime.alignMemory(type.flatSize); // final padding at end
-          }
           type.needsFlattening = (this.flatFactor != 1);
           dprint('types', 'type: ' + type.name_ + ' : ' + JSON.stringify(type.fields));
           dprint('types', '                        has final size of ' + type.flatSize + ', flatting: ' + type.needsFlattening + ' ? ' + (type.flatFactor ? type.flatFactor : JSON.stringify(type.flatIndexes)));