Switch allocation size expression analysis to unconverted result expression.

Author: criemen

cpp/ql/src/experimental/library/ArrayLengthAnalysis.qll

@@ -219,11 +219,11 @@ private predicate allocation(Instruction array, Length length, int delta) {
       (
         exists(Expr lengthExpr |
           deconstructMallocSizeExpr(alloc.getSizeExpr(), lengthExpr, delta) and
-          length.(VNLength).getInstruction().getConvertedResultExpression() = lengthExpr
+          length.(VNLength).getInstruction().getUnconvertedResultExpression() = lengthExpr
         )
         or
         not exists(int d | deconstructMallocSizeExpr(alloc.getSizeExpr(), _, d)) and
-        length.(VNLength).getInstruction().getConvertedResultExpression() = alloc.getSizeExpr() and
+        length.(VNLength).getInstruction().getUnconvertedResultExpression() = alloc.getSizeExpr() and
         delta = 0
       )
     )

cpp/ql/test/experimental/library-tests/arraylengthanalysis/ArrayLengthAnalysisTest.expected

@@ -1,12 +1,17 @@
 | test.cpp:15:8:15:11 | Load: aptr | VNLength(InitializeParameter: count) | 0 | ZeroOffset | 0 |
 | test.cpp:19:8:19:8 | Load: a | VNLength(Chi: ptr) | 0 | ZeroOffset | 0 |
+| test.cpp:19:8:19:8 | Load: a | VNLength(Convert: (unsigned long)...) | 0 | ZeroOffset | 0 |
 | test.cpp:21:8:21:8 | Load: a | VNLength(Chi: ptr) | -1 | ZeroOffset | 0 |
 | test.cpp:23:8:23:8 | Load: a | VNLength(Chi: ptr) | 1 | ZeroOffset | 0 |
 | test.cpp:27:8:27:8 | Load: c | VNLength(Chi: ptr) | 0 | ZeroOffset | 0 |
+| test.cpp:27:8:27:8 | Load: c | VNLength(Convert: (unsigned long)...) | 0 | ZeroOffset | 0 |
 | test.cpp:28:8:28:24 | Convert: (unsigned char *)... | VNLength(Chi: ptr) | 0 | ZeroOffset | 0 |
+| test.cpp:28:8:28:24 | Convert: (unsigned char *)... | VNLength(Convert: (unsigned long)...) | 0 | ZeroOffset | 0 |
 | test.cpp:30:8:30:8 | Load: v | VNLength(Chi: ptr) | 0 | ZeroOffset | 0 |
+| test.cpp:30:8:30:8 | Load: v | VNLength(Convert: (unsigned long)...) | 0 | ZeroOffset | 0 |
 | test.cpp:34:8:34:12 | Convert: array to pointer conversion | ZeroLength | 100 | ZeroOffset | 0 |
 | test.cpp:37:10:37:10 | Load: b | VNLength(Chi: ptr) | 0 | ZeroOffset | 0 |
+| test.cpp:37:10:37:10 | Load: b | VNLength(Convert: (unsigned long)...) | 0 | ZeroOffset | 0 |
 | test.cpp:44:8:44:8 | Load: a | VNLength(InitializeParameter: count) | 0 | ZeroOffset | 2 |
 | test.cpp:53:10:53:10 | Load: a | VNLength(InitializeParameter: count) | 0 | ZeroOffset | 2 |
 | test.cpp:56:10:56:10 | Load: a | VNLength(InitializeParameter: count) | 0 | ZeroOffset | 3 |