ASSERT type_is_instr in multiple drcachesim tests (tool.reuse_distance,tool.drcachesim.warmup-zeros,tool.drcachesim.missfile) on appveyor

The 32-bit version failed once: https://ci.appveyor.com/project/DynamoRIO/dynamorio/builds/21162519

[00:09:36] test 213
[00:09:36]         Start 213: code_api|tool.reuse_distance
[00:09:36] 
[00:09:36] 213: Test command: C:\projects\dynamorio\build\build_debug-internal-32\bin32\drrun.exe "-s" "90" "-quiet" "-debug" "-use_dll" "C:/projects/dynamorio/build/build_debug-internal-32/lib32/debug/dynamorio.dll" "-exit0" "-stderr_mask" "0xC" "-msgbox_mask" "0" "-dumpcore_mask" "0x7d" "-staged" "-code_api" "-t" "drcachesim" "-ipc_name" "drtestpipe_reuse_distance" "-simulator_type" "reuse_distance" "-reuse_distance_threshold" "256" "--" "C:/projects/dynamorio/build/build_debug-internal-32/suite/tests/bin/simple_app.exe"
[00:09:36] 213: Test timeout computed to be: 600
[00:09:36] 213: Hello, world!
[00:09:36] 213: Assertion failed: type_is_instr(cur_ref.instr.type), file ..\..\clients\drcachesim\reader\reader.cpp, line 132