srctree

Andrew Kelley parent 1c9bb6a7 a69788ba
std.Build.Step.CheckObject: fix parseDumpNames

This function incorrectly assumed that module name subsections, functionname subsections, and local name subsections are encoded the same,however according to[the specification](https://webassembly.github.io/spec/core/appendix/custom.html)they are encoded differently.

This commit adds support for parsing module name subsections correctly,which started appearing after upgrading to LLVM 18.

inlinesplit
lib/std/Build/Step/CheckObject.zig added: 58, removed: 32, total 26
@@ -2475,12 +2475,12 @@ const WasmDumper = struct {
try writer.print("params {d}\n", .{params});
var index: u32 = 0;
while (index < params) : (index += 1) {
try parseDumpType(step, std.wasm.Valtype, reader, writer);
_ = try parseDumpType(step, std.wasm.Valtype, reader, writer);
} else index = 0;
const returns = try std.leb.readULEB128(u32, reader);
try writer.print("returns {d}\n", .{returns});
while (index < returns) : (index += 1) {
try parseDumpType(step, std.wasm.Valtype, reader, writer);
_ = try parseDumpType(step, std.wasm.Valtype, reader, writer);
}
}
},
@@ -2512,11 +2512,11 @@ const WasmDumper = struct {
try parseDumpLimits(reader, writer);
},
.global => {
try parseDumpType(step, std.wasm.Valtype, reader, writer);
_ = try parseDumpType(step, std.wasm.Valtype, reader, writer);
try writer.print("mutable {}\n", .{0x01 == try std.leb.readULEB128(u32, reader)});
},
.table => {
try parseDumpType(step, std.wasm.RefType, reader, writer);
_ = try parseDumpType(step, std.wasm.RefType, reader, writer);
try parseDumpLimits(reader, writer);
},
}
@@ -2531,7 +2531,7 @@ const WasmDumper = struct {
.table => {
var i: u32 = 0;
while (i < entries) : (i += 1) {
try parseDumpType(step, std.wasm.RefType, reader, writer);
_ = try parseDumpType(step, std.wasm.RefType, reader, writer);
try parseDumpLimits(reader, writer);
}
},
@@ -2544,7 +2544,7 @@ const WasmDumper = struct {
.global => {
var i: u32 = 0;
while (i < entries) : (i += 1) {
try parseDumpType(step, std.wasm.Valtype, reader, writer);
_ = try parseDumpType(step, std.wasm.Valtype, reader, writer);
try writer.print("mutable {}\n", .{0x01 == try std.leb.readULEB128(u1, reader)});
try parseDumpInit(step, reader, writer);
}
@@ -2605,12 +2605,13 @@ const WasmDumper = struct {
}
}
 
fn parseDumpType(step: *Step, comptime WasmType: type, reader: anytype, writer: anytype) !void {
const type_byte = try reader.readByte();
const valtype = std.meta.intToEnum(WasmType, type_byte) catch {
return step.fail("Invalid wasm type value '{d}'", .{type_byte});
fn parseDumpType(step: *Step, comptime E: type, reader: anytype, writer: anytype) !E {
const byte = try reader.readByte();
const tag = std.meta.intToEnum(E, byte) catch {
return step.fail("invalid wasm type value '{d}'", .{byte});
};
try writer.print("type {s}\n", .{@tagName(valtype)});
try writer.print("type {s}\n", .{@tagName(tag)});
return tag;
}
 
fn parseDumpLimits(reader: anytype, writer: anytype) !void {
@@ -2642,29 +2643,54 @@ const WasmDumper = struct {
}
}
 
/// https://webassembly.github.io/spec/core/appendix/custom.html
fn parseDumpNames(step: *Step, reader: anytype, writer: anytype, data: []const u8) !void {
while (reader.context.pos < data.len) {
try parseDumpType(step, std.wasm.NameSubsection, reader, writer);
const size = try std.leb.readULEB128(u32, reader);
const entries = try std.leb.readULEB128(u32, reader);
try writer.print(
\\size {d}
\\names {d}
, .{ size, entries });
try writer.writeByte('\n');
var i: u32 = 0;
while (i < entries) : (i += 1) {
const index = try std.leb.readULEB128(u32, reader);
const name_len = try std.leb.readULEB128(u32, reader);
const pos = reader.context.pos;
const name = data[pos..][0..name_len];
reader.context.pos += name_len;
switch (try parseDumpType(step, std.wasm.NameSubsection, reader, writer)) {
// The module name subsection ... consists of a single name
// that is assigned to the module itself.
.module => {
const size = try std.leb.readULEB128(u32, reader);
const name_len = try std.leb.readULEB128(u32, reader);
if (size != name_len + 1) return error.BadSubsectionSize;
if (reader.context.pos + name_len > data.len) return error.UnexpectedEndOfStream;
try writer.print("name {s}\n", .{data[reader.context.pos..][0..name_len]});
reader.context.pos += name_len;
},
 
try writer.print(
\\index {d}
\\name {s}
, .{ index, name });
try writer.writeByte('\n');
// The function name subsection ... consists of a name map
// assigning function names to function indices.
.function, .global, .data_segment => {
const size = try std.leb.readULEB128(u32, reader);
const entries = try std.leb.readULEB128(u32, reader);
try writer.print(
\\size {d}
\\names {d}
\\
, .{ size, entries });
for (0..entries) |_| {
const index = try std.leb.readULEB128(u32, reader);
const name_len = try std.leb.readULEB128(u32, reader);
if (reader.context.pos + name_len > data.len) return error.UnexpectedEndOfStream;
const name = data[reader.context.pos..][0..name_len];
reader.context.pos += name.len;
 
try writer.print(
\\index {d}
\\name {s}
\\
, .{ index, name });
}
},
 
// The local name subsection ... consists of an indirect name
// map assigning local names to local indices grouped by
// function indices.
.local => {
return step.fail("TODO implement parseDumpNames for local subsections", .{});
},
 
else => |t| return step.fail("invalid subsection type: {s}", .{@tagName(t)}),
}
}
}