mirror/zig
1
0
Fork 0
mirror of https://github.com/ziglang/zig.git synced 2025-12-25 07:33:08 +00:00
Code Issues Packages Projects Releases Wiki Activity

Fix TLS for VariantI arches with a twist

Browse Source
This commit is contained in:
LemonBoy 2019-09-21 23:10:45 +02:00 committed by Andrew Kelley
parent 4dd17a7c9e
commit a11c20e26a
1 changed files with 14 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

19
std/os/linux/tls.zig
View File

@ -47,7 +47,7 @@ const TLSVariant = enum {
};
const tls_variant = switch (builtin.arch) {
.arm, .armeb, .aarch64, .aarch64_be, .riscv32, .riscv64 => TLSVariant.VariantI,
.arm, .armeb, .aarch64, .aarch64_be, .riscv32, .riscv64, .mipsel => TLSVariant.VariantI,
.x86_64, .i386 => TLSVariant.VariantII,
else => @compileError("undefined tls_variant for this architecture"),
};
@ -57,8 +57,7 @@ const tls_tcb_size = switch (builtin.arch) {
// ARM EABI mandates enough space for two pointers: the first one points to
// the DTV while the second one is unspecified but reserved
.arm, .armeb, .aarch64, .aarch64_be => 2 * @sizeOf(usize),
.i386, .x86_64 => @sizeOf(usize),
else => 0,
else => @sizeOf(usize),
};
// Controls if the TCB should be aligned according to the TLS segment p_align
@ -67,6 +66,12 @@ const tls_tcb_align_size = switch (builtin.arch) {
else => false,
};
// Controls if the TP points to the end of the TCB instead of its beginning
const tls_tp_points_past_tcb = switch (builtin.arch) {
.riscv32, .riscv64, .mipsel, .powerpc64, .powerpc64le => true,
else => false,
};
// Check if the architecture-specific parameters look correct
comptime {
if (tls_tcb_align_size and tls_variant != TLSVariant.VariantI) {
@ -78,10 +83,12 @@ comptime {
// make the generated code more efficient
const tls_tp_offset = switch (builtin.arch) {
.mipsel => 0x7000,
else => 0,
};
const tls_dtv_offset = switch (builtin.arch) {
.mipsel => 0x8000,
else => 0,
};
@ -119,7 +126,8 @@ pub fn setThreadPointer(addr: usize) void {
);
},
.arm => |arm| {
_ = std.os.linux.syscall1(std.os.linux.SYS_set_tls, addr);
const rc = std.os.linux.syscall1(std.os.linux.SYS_set_tls, addr);
assert(rc == 0);
},
.riscv64 => {
asm volatile (
@ -251,7 +259,8 @@ pub fn copyTLS(addr: usize) usize {
@memcpy(@intToPtr([*]u8, addr + tls_img.data_offset), tls_img.data_src.ptr, tls_img.data_src.len);
// Return the corrected (if needed) value for the tp register
return addr + tls_img.tcb_offset + tls_tp_offset;
return addr + tls_tp_offset +
if (tls_tp_points_past_tcb) tls_img.data_offset else tls_img.tcb_offset;
}
var main_thread_tls_buffer: [256]u8 align(32) = undefined;