[wasm] Write fuzzers for single wasm sections.

src/flag-definitions.h

Index: src/flag-definitions.h
diff --git a/src/flag-definitions.h b/src/flag-definitions.h
index a341e33c6f053711c48b75724997e288f1f06b0d..b53400d21208a51b83311c11ed88518b4e98dde3 100644
--- a/src/flag-definitions.h
+++ b/src/flag-definitions.h
@@ -1093,6 +1093,18 @@ DEFINE_STRING(redirect_code_traces_to, NULL,
 DEFINE_BOOL(hydrogen_track_positions, false,
             "track source code positions when building IR")
 
+// Parameters for the wasm-section-fuzzer, not used by V8.

[Michael Starzinger, 2016/09/13 09:27:08]

We already employ a similar solution for some "d8-only" flags, that are not
respected for other embedders besides the "d8" binary. The section is currently
called "Dev shell flags" in this file.

nit: Can we move this section close to the other, and also clean up the section
headers somehow so that both specifically mention the name of the binary for
which they are used? Something along the lines of ...

//
// Specific flags for {d8}, not used within V8 proper.
//

[...]

//
// Specific flags for {v8_simple_wasm_fuzzer}, not used within V8 proper.
//

[...]

[ahaas, 2016/09/13 09:50:22]

Done.

+DEFINE_BOOL(wasm_fuzz_types, false, "fuzz the types section of a wasm module")
+DEFINE_BOOL(wasm_fuzz_names, false, "fuzz the names section of a wasm module")
+DEFINE_BOOL(wasm_fuzz_globals, false,
+            "fuzz the globals section of a wasm module")
+DEFINE_BOOL(wasm_fuzz_imports, false,
+            "fuzz the imports section of a wasm module")
+DEFINE_BOOL(wasm_fuzz_function_sigs, false,
+            "fuzz the function signatures section of a wasm module")
+DEFINE_BOOL(wasm_fuzz_memory, false, "fuzz the memory section of a wasm module")
+DEFINE_BOOL(wasm_fuzz_data, false, "fuzz the data section of a wasm module")
+
 //
 // Disassembler only flags
 //