mirror/zig
1
0
Fork 0
mirror of https://github.com/ziglang/zig.git synced 2025-12-06 06:13:07 +00:00
Code Issues Packages Projects Releases Wiki Activity

debug: add relocateContext

Browse Source 
dwarf: fixup tests that used a ThreadContext
This commit is contained in:
kcbanner 2023-07-09 14:45:34 -04:00
parent 94354aa6aa
commit 203d96ae97
3 changed files with 69 additions and 55 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

96
lib/std/debug.zig
View File

@ -133,6 +133,12 @@ pub fn dumpCurrentStackTrace(start_addr: ?usize) void {
}
}
pub const have_ucontext = @hasDecl(os.system, "ucontext_t") and
(builtin.os.tag != .linux or switch (builtin.cpu.arch) {
.mips, .mipsel, .mips64, .mips64el, .riscv64 => false,
else => true,
});
/// Platform-specific thread state. This contains register state, and on some platforms
/// information about the stack. This is not safe to trivially copy, because some platforms
/// use internal pointers within this structure. To make a copy, use `copyContext`.
@ -146,6 +152,47 @@ pub const ThreadContext = blk: {
}
};
/// Copies one context to another, updating any internal pointers
pub fn copyContext(source: *const ThreadContext, dest: *ThreadContext) void {
if (!have_ucontext) return {};
dest.* = source.*;
relocateContext(dest);
}
/// Updates any internal points in the context to reflect its current location
pub fn relocateContext(context: *ThreadContext) void {
return switch (native_os) {
.macos => {
context.mcontext = &context.__mcontext_data;
},
else => {},
};
}
pub const have_getcontext = @hasDecl(os.system, "getcontext") and
(builtin.os.tag != .linux or switch (builtin.cpu.arch) {
.x86, .x86_64 => true,
else => false,
});
/// Capture the current context. The register values in the context will reflect the
/// state after the platform `getcontext` function returned.
///
/// It is valid to call this if the platform doesn't have context capturing support,
/// in that case false will be returned.
pub inline fn getContext(context: *ThreadContext) bool {
if (native_os == .windows) {
context.* = std.mem.zeroes(windows.CONTEXT);
windows.ntdll.RtlCaptureContext(context);
return true;
}
const result = have_getcontext and os.system.getcontext(context) == 0;
if (native_os == .macos) assert(context.mcsize == @sizeOf(std.c.mcontext_t));
return result;
}
/// Tries to print the stack trace starting from the supplied base pointer to stderr,
/// unbuffered, and ignores any error returned.
/// TODO multithreaded awareness
@ -428,51 +475,6 @@ pub fn writeStackTrace(
}
}
pub const have_getcontext = @hasDecl(os.system, "getcontext") and
(builtin.os.tag != .linux or switch (builtin.cpu.arch) {
.x86, .x86_64 => true,
else => false,
});
pub const have_ucontext = @hasDecl(os.system, "ucontext_t") and
(builtin.os.tag != .linux or switch (builtin.cpu.arch) {
.mips, .mipsel, .mips64, .mips64el, .riscv64 => false,
else => true,
});
pub inline fn getContext(context: *ThreadContext) bool {
if (native_os == .windows) {
context.* = std.mem.zeroes(windows.CONTEXT);
windows.ntdll.RtlCaptureContext(context);
return true;
}
const result = have_getcontext and os.system.getcontext(context) == 0;
if (native_os == .macos) {
// TODO: Temp, to discover this size via aarch64 CI
if (context.mcsize != @sizeOf(std.c.mcontext_t)) {
print("context.mcsize does not match! {} vs {}\n", .{ context.mcsize, @sizeOf(std.c.mcontext_t) });
}
assert(context.mcsize == @sizeOf(std.c.mcontext_t));
}
return result;
}
pub fn copyContext(source: *const ThreadContext, dest: *ThreadContext) void {
if (native_os == .windows) dest.* = source.*;
if (!have_ucontext) return {};
return switch (native_os) {
.macos => {
dest.* = source.*;
dest.mcontext = &dest.__mcontext_data;
},
else => dest.* = source.*,
};
}
pub const UnwindError = if (have_ucontext)
@typeInfo(@typeInfo(@TypeOf(StackIterator.next_unwind)).Fn.return_type.?).ErrorUnion.error_set
else
@ -855,7 +857,7 @@ fn printUnknownSource(debug_info: *DebugInfo, out_stream: anytype, address: usiz
pub fn printUnwindError(debug_info: *DebugInfo, out_stream: anytype, address: usize, err: UnwindError, tty_config: io.tty.Config) !void {
const module_name = debug_info.getModuleNameForAddress(address) orelse "???";
try tty_config.setColor(out_stream, .dim);
try out_stream.print("Unwind information for {s} was not available ({}), trace may be incomplete\n\n", .{ module_name, err });
try out_stream.print("Unwind information for `{s}` was not available ({}), trace may be incomplete\n\n", .{ module_name, err });
try tty_config.setColor(out_stream, .reset);
}
@ -1641,7 +1643,7 @@ pub const DebugInfo = struct {
const seg_start = segment_cmd.vmaddr;
const seg_end = seg_start + segment_cmd.vmsize;
if (original_address >= seg_start and original_address < seg_end) {
return mem.sliceTo(std.c._dyld_get_image_name(i), 0);
return fs.path.basename(mem.sliceTo(std.c._dyld_get_image_name(i), 0));
}
},
else => {},

13
lib/std/dwarf/expressions.zig
View File

@ -48,6 +48,7 @@ pub const ExpressionOptions = struct {
call_frame_context: bool = false,
};
// Explcitly defined to support executing sub-expressions
pub const ExpressionError = error{
UnimplementedExpressionCall,
UnimplementedOpcode,
@ -1178,20 +1179,21 @@ test "DWARF expressions" {
.is_macho = builtin.os.tag == .macos,
};
var thread_context: std.debug.ThreadContext = undefined;
std.debug.relocateContext(&thread_context);
const context = ExpressionContext{
.thread_context = &thread_context,
.reg_context = reg_context,
};
// Only test register operations on arch / os that have them implemented
if (abi.regBytes(&thread_context, 0, reg_context)) |_| {
if (abi.regBytes(&thread_context, 0, reg_context)) |reg_bytes| {
// TODO: Test fbreg (once implemented): mock a DIE and point compile_unit.frame_base at it
mem.writeIntSliceNative(usize, try abi.regBytes(&thread_context, 0, reg_context), 0xee);
mem.writeIntSliceNative(usize, try abi.regBytes(&thread_context, abi.fpRegNum(reg_context), reg_context), 1);
mem.writeIntSliceNative(usize, try abi.regBytes(&thread_context, abi.spRegNum(reg_context), reg_context), 2);
mem.writeIntSliceNative(usize, try abi.regBytes(&thread_context, abi.ipRegNum(), reg_context), 3);
mem.writeIntSliceNative(usize, reg_bytes, 0xee);
(try abi.regValueNative(usize, &thread_context, abi.fpRegNum(reg_context), reg_context)).* = 1;
(try abi.regValueNative(usize, &thread_context, abi.spRegNum(reg_context), reg_context)).* = 2;
(try abi.regValueNative(usize, &thread_context, abi.ipRegNum(), reg_context)).* = 3;
try b.writeBreg(writer, abi.fpRegNum(reg_context), @as(usize, 100));
try b.writeBreg(writer, abi.spRegNum(reg_context), @as(usize, 200));
@ -1609,6 +1611,7 @@ test "DWARF expressions" {
.is_macho = builtin.os.tag == .macos,
};
var thread_context: std.debug.ThreadContext = undefined;
std.debug.relocateContext(&thread_context);
context = ExpressionContext{
.thread_context = &thread_context,
.reg_context = reg_context,

15
test/standalone/dwarf_unwinding/zig_unwind.zig
View File

@ -19,9 +19,19 @@ noinline fn frame3(expected: *[4]usize, unwound: *[4]usize) void {
}
noinline fn frame2(expected: *[4]usize, unwound: *[4]usize) void {
if (builtin.os.tag == .macos) {
// Excercise different __unwind_info encodings by forcing some registers to be restored
// Excercise different __unwind_info / DWARF CFI encodings by forcing some registers to be restored
if (builtin.target.ofmt != .c) {
switch (builtin.cpu.arch) {
.x86 => {
asm volatile (
\\movl $3, %%ebx
\\movl $1, %%ecx
\\movl $2, %%edx
\\movl $7, %%edi
\\movl $6, %%esi
\\movl $5, %%ebp
::: "ebx", "ecx", "edx", "edi", "esi", "ebp");
},
.x86_64 => {
asm volatile (
\\movq $3, %%rbx
@ -32,7 +42,6 @@ noinline fn frame2(expected: *[4]usize, unwound: *[4]usize) void {
\\movq $6, %%rbp
::: "rbx", "r12", "r13", "r14", "r15", "rbp");
},
.aarch64 => {},
else => {},
}
}