Commit 2d005827b874f27535cda72c80b6558d9d4cd30c | zig

author	Andrew Kelley <andrew@ziglang.org> 2024-09-09 21:16:06-07:00
committer	Andrew Kelley <andrew@ziglang.org> 2024-09-11 13:41:29-07:00
log	2d005827b874f27535cda72c80b6558d9d4cd30c
tree	9080004df76b836ff98416e1779bdcd85677ffd9
parent	0cdccff51912359b7ec5afa57fbbd5bb69d8f3a2

This value is useful to help determine run uniqueness in the face of
recursion, however it is not valuable to expose to the fuzzing UI.

6 files changed, 3 insertions(+), 17 deletions(-)

lib/fuzzer.zig+3-3

...	...	@@ -28,7 +28,8 @@ fn logOverride(
28	28	f.writer().print(prefix1 ++ prefix2 ++ format ++ "\n", args) catch @panic("failed to write to fuzzer log");
29	29	}
30	30
31		export threadlocal var __sancov_lowest_stack: usize = std.math.maxInt(usize);
	31	/// Helps determine run uniqueness in the face of recursion.
	32	export threadlocal var __sancov_lowest_stack: usize = 0;
32	33
33	34	export fn __sanitizer_cov_trace_const_cmp1(arg1: u8, arg2: u8) void {
34	35	handleCmp(@returnAddress(), arg1, arg2);
...	...	@@ -220,7 +221,6 @@ const Fuzzer = struct {
220	221	.n_runs = 0,
221	222	.unique_runs = 0,
222	223	.pcs_len = pcs.len,
223		.lowest_stack = std.math.maxInt(usize),
224	224	};
225	225	f.seen_pcs.appendSliceAssumeCapacity(std.mem.asBytes(&header));
226	226	f.seen_pcs.appendNTimesAssumeCapacity(0, n_bitset_elems * @sizeOf(usize));
...	...	@@ -261,8 +261,8 @@ const Fuzzer = struct {
261	261	f.input.appendSliceAssumeCapacity(run.input);
262	262	try f.mutate();
263	263
264		_ = @atomicRmw(usize, &header.lowest_stack, .Min, __sancov_lowest_stack, .monotonic);
265	264	@memset(f.pc_counters, 0);
	265	__sancov_lowest_stack = std.math.maxInt(usize);
266	266	f.coverage.reset();
267	267
268	268	fuzzer_one(f.input.items.ptr, f.input.items.len);

lib/fuzzer/web/index.html-1

...	...	@@ -147,7 +147,6 @@
147	147	<li>Total Runs: <span id="statTotalRuns"></span></li>
148	148	<li>Unique Runs: <span id="statUniqueRuns"></span></li>
149	149	<li>Coverage: <span id="statCoverage"></span></li>
150		<li>Lowest Stack: <span id="statLowestStack"></span></li>
151	150	<li>Entry Points: <ul id="entryPointsList"></ul></li>
152	151	</ul>
153	152	</div>

lib/fuzzer/web/main.js-2

...	...	@@ -6,7 +6,6 @@
6	6	const domStatTotalRuns = document.getElementById("statTotalRuns");
7	7	const domStatUniqueRuns = document.getElementById("statUniqueRuns");
8	8	const domStatCoverage = document.getElementById("statCoverage");
9		const domStatLowestStack = document.getElementById("statLowestStack");
10	9	const domEntryPointsList = document.getElementById("entryPointsList");
11	10
12	11	let wasm_promise = fetch("main.wasm");
...	...	@@ -158,7 +157,6 @@
158	157	domStatTotalRuns.innerText = totalRuns;
159	158	domStatUniqueRuns.innerText = uniqueRuns + " (" + percent(uniqueRuns, totalRuns) + "%)";
160	159	domStatCoverage.innerText = coveredSourceLocations + " / " + totalSourceLocations + " (" + percent(coveredSourceLocations, totalSourceLocations) + "%)";
161		domStatLowestStack.innerText = unwrapString(wasm_exports.lowestStack());
162	160
163	161	const entryPoints = unwrapInt32Array(wasm_exports.entryPoints());
164	162	resizeDomList(domEntryPointsList, entryPoints.length, "<li></li>");

lib/fuzzer/web/main.zig-7

...	...	@@ -106,13 +106,6 @@ export fn decl_source_html(decl_index: Decl.Index) String {
106	106	return String.init(string_result.items);
107	107	}
108	108
109		export fn lowestStack() String {
110		const header: *abi.CoverageUpdateHeader = @ptrCast(recent_coverage_update.items[0..@sizeOf(abi.CoverageUpdateHeader)]);
111		string_result.clearRetainingCapacity();
112		string_result.writer(gpa).print("0x{d}", .{header.lowest_stack}) catch @panic("OOM");
113		return String.init(string_result.items);
114		}
115
116	109	export fn totalSourceLocations() usize {
117	110	return coverage_source_locations.items.len;
118	111	}

lib/std/Build/Fuzz/WebServer.zig-2

...	...	@@ -406,7 +406,6 @@ fn sendCoverageContext(
406	406	const seen_pcs = cov_header.seenBits();
407	407	const n_runs = @atomicLoad(usize, &cov_header.n_runs, .monotonic);
408	408	const unique_runs = @atomicLoad(usize, &cov_header.unique_runs, .monotonic);
409		const lowest_stack = @atomicLoad(usize, &cov_header.lowest_stack, .monotonic);
410	409	if (prev_unique_runs.* != unique_runs) {
411	410	// There has been an update.
412	411	if (prev_unique_runs.* == 0) {
...	...	@@ -431,7 +430,6 @@ fn sendCoverageContext(
431	430	const header: abi.CoverageUpdateHeader = .{
432	431	.n_runs = n_runs,
433	432	.unique_runs = unique_runs,
434		.lowest_stack = lowest_stack,
435	433	};
436	434	const iovecs: [2]std.posix.iovec_const = .{
437	435	makeIov(std.mem.asBytes(&header)),

lib/std/Build/Fuzz/abi.zig-2

...	...	@@ -13,7 +13,6 @@ pub const SeenPcsHeader = extern struct {
13	13	n_runs: usize,
14	14	unique_runs: usize,
15	15	pcs_len: usize,
16		lowest_stack: usize,
17	16
18	17	/// Used for comptime assertions. Provides a mechanism for strategically
19	18	/// causing compile errors.
...	...	@@ -79,7 +78,6 @@ pub const CoverageUpdateHeader = extern struct {
79	78	flags: Flags = .{},
80	79	n_runs: u64,
81	80	unique_runs: u64,
82		lowest_stack: u64,
83	81
84	82	pub const Flags = packed struct(u64) {
85	83	tag: ToClientTag = .coverage_update,