[vm/ffi] Make overflow checks consistent - fix asan

Moves a test that tries to allocate a too large amount of memory to a file which is not executed on asan.

Fixes: #37388

Change-Id: I91101c05be509b670ff9ba82ee25424554468ec5
Cq-Include-Trybots: luci.dart.try:vm-kernel-asan-linux-release-x64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/107508
Commit-Queue: Daco Harkes <[email protected]>
Auto-Submit: Daco Harkes <[email protected]>
Reviewed-by: Teagan Strickland <[email protected]>

Author: dcharkes

tests/ffi/data_not_asan_test.dart

@@ -3,9 +3,8 @@
 // BSD-style license that can be found in the LICENSE file.
 //
 // Dart test program for testing dart:ffi primitive data pointers.
-// This test tries to allocate too much memory on purpose to test the Exception
-// thrown on malloc failing.
-// This malloc also triggers an asan alarm, so this test is in a separate file
+//
+// These mallocs trigger an asan alarm, so these tests are in a separate file
 // which is excluded in asan mode.
 
 library FfiTest;
@@ -16,14 +15,22 @@ import "package:expect/expect.dart";
 
 void main() {
   testPointerAllocateTooLarge();
+  testPointerAllocateNegative();
 }
 
-/// This test is skipped in asan mode.
 void testPointerAllocateTooLarge() {
+  // Try to allocate something that doesn't fit in 64 bit address space.
   int maxInt = 9223372036854775807; // 2^63 - 1
-  Expect.throws(
-      () => ffi.allocate<ffi.Int64>(count: maxInt)); // does not fit in range
+  Expect.throws(() => ffi.allocate<ffi.Int64>(count: maxInt));
+
+  // Try to allocate almost the full 64 bit address space.
   int maxInt1_8 = 1152921504606846975; // 2^60 -1
-  Expect.throws(
-      () => ffi.allocate<ffi.Int64>(count: maxInt1_8)); // not enough memory
+  Expect.throws(() => ffi.allocate<ffi.Int64>(count: maxInt1_8));
+}
+
+void testPointerAllocateNegative() {
+  // Passing in -1 will be converted into an unsigned integer. So, it will try
+  // to allocate SIZE_MAX - 1 + 1 bytes. This will fail as it is the max amount
+  // of addressable memory on the system.
+  Expect.throws(() => ffi.allocate<ffi.Int8>(count: -1));
 }

tests/ffi/data_test.dart

@@ -15,7 +15,7 @@ void main() {
   testPointerFromPointer();
   testPointerPointerArithmetic();
   testPointerPointerArithmeticSizes();
-  testPointerAllocateNonPositive();
+  testPointerAllocateZero();
   testPointerCast();
   testCastGeneric();
   testCastGeneric2();
@@ -92,7 +92,7 @@ void testPointerPointerArithmeticSizes() {
   p3.free();
 }
 
-void testPointerAllocateNonPositive() {
+void testPointerAllocateZero() {
   // > If size is 0, either a null pointer or a unique pointer that can be
   // > successfully passed to free() shall be returned.
   // http://pubs.opengroup.org/onlinepubs/009695399/functions/malloc.html
@@ -108,11 +108,6 @@ void testPointerAllocateNonPositive() {
   if (!returnedNullPointer) {
     p.free();
   }
-
-  // Passing in -1 will be converted into an unsigned integer. So, it will try
-  // to allocate SIZE_MAX - 1 + 1 bytes. This will fail as it is the max amount
-  // of addressable memory on the system.
-  Expect.throws(() => ffi.allocate<ffi.Int8>(count: -1));
 }
 
 void testPointerCast() {