Files
zig/src/print_air.zig
mlugg d0e74ffe52 compiler: rework comptime pointer representation and access
We've got a big one here! This commit reworks how we represent pointers
in the InternPool, and rewrites the logic for loading and storing from
them at comptime.

Firstly, the pointer representation. Previously, pointers were
represented in a highly structured manner: pointers to fields, array
elements, etc, were explicitly represented. This works well for simple
cases, but is quite difficult to handle in the cases of unusual
reinterpretations, pointer casts, offsets, etc. Therefore, pointers are
now represented in a more "flat" manner. For types without well-defined
layouts -- such as comptime-only types, automatic-layout aggregates, and
so on -- we still use this "hierarchical" structure. However, for types
with well-defined layouts, we use a byte offset associated with the
pointer. This allows the comptime pointer access logic to deal with
reinterpreted pointers far more gracefully, because the "base address"
of a pointer -- for instance a `field` -- is a single value which
pointer accesses cannot exceed since the parent has undefined layout.
This strategy is also more useful to most backends -- see the updated
logic in `codegen.zig` and `codegen/llvm.zig`. For backends which do
prefer a chain of field and elements accesses for lowering pointer
values, such as SPIR-V, there is a helpful function in `Value` which
creates a strategy to derive a pointer value using ideally only field
and element accesses. This is actually more correct than the previous
logic, since it correctly handles pointer casts which, after the dust
has settled, end up referring exactly to an aggregate field or array
element.

In terms of the pointer access code, it has been rewritten from the
ground up. The old logic had become rather a mess of special cases being
added whenever bugs were hit, and was still riddled with bugs. The new
logic was written to handle the "difficult" cases correctly, the most
notable of which is restructuring of a comptime-only array (for
instance, converting a `[3][2]comptime_int` to a `[2][3]comptime_int`.
Currently, the logic for loading and storing work somewhat differently,
but a future change will likely improve the loading logic to bring it
more in line with the store strategy. As far as I can tell, the rewrite
has fixed all bugs exposed by #19414.

As a part of this, the comptime bitcast logic has also been rewritten.
Previously, bitcasts simply worked by serializing the entire value into
an in-memory buffer, then deserializing it. This strategy has two key
weaknesses: pointers, and undefined values. Representations of these
values at comptime cannot be easily serialized/deserialized whilst
preserving data, which means many bitcasts would become runtime-known if
pointers were involved, or would turn `undefined` values into `0xAA`.
The new logic works by "flattening" the datastructure to be cast into a
sequence of bit-packed atomic values, and then "unflattening" it; using
serialization when necessary, but with special handling for `undefined`
values and for pointers which align in virtual memory. The resulting
code is definitely slower -- more on this later -- but it is correct.

The pointer access and bitcast logic required some helper functions and
types which are not generally useful elsewhere, so I opted to split them
into separate files `Sema/comptime_ptr_access.zig` and
`Sema/bitcast.zig`, with simple re-exports in `Sema.zig` for their small
public APIs.

Whilst working on this branch, I caught various unrelated bugs with
transitive Sema errors, and with the handling of `undefined` values.
These bugs have been fixed, and corresponding behavior test added.

In terms of performance, I do anticipate that this commit will regress
performance somewhat, because the new pointer access and bitcast logic
is necessarily more complex. I have not yet taken performance
measurements, but will do shortly, and post the results in this PR. If
the performance regression is severe, I will do work to to optimize the
new logic before merge.

Resolves: #19452
Resolves: #19460
2024-04-17 13:41:25 +01:00

977 lines
36 KiB
Zig

const std = @import("std");
const Allocator = std.mem.Allocator;
const fmtIntSizeBin = std.fmt.fmtIntSizeBin;
const Module = @import("Module.zig");
const Value = @import("Value.zig");
const Type = @import("type.zig").Type;
const Air = @import("Air.zig");
const Liveness = @import("Liveness.zig");
const InternPool = @import("InternPool.zig");
pub fn write(stream: anytype, module: *Module, air: Air, liveness: ?Liveness) void {
const instruction_bytes = air.instructions.len *
// Here we don't use @sizeOf(Air.Inst.Data) because it would include
// the debug safety tag but we want to measure release size.
(@sizeOf(Air.Inst.Tag) + 8);
const extra_bytes = air.extra.len * @sizeOf(u32);
const tomb_bytes = if (liveness) |l| l.tomb_bits.len * @sizeOf(usize) else 0;
const liveness_extra_bytes = if (liveness) |l| l.extra.len * @sizeOf(u32) else 0;
const liveness_special_bytes = if (liveness) |l| l.special.count() * 8 else 0;
const total_bytes = @sizeOf(Air) + instruction_bytes + extra_bytes +
@sizeOf(Liveness) + liveness_extra_bytes +
liveness_special_bytes + tomb_bytes;
// zig fmt: off
stream.print(
\\# Total AIR+Liveness bytes: {}
\\# AIR Instructions: {d} ({})
\\# AIR Extra Data: {d} ({})
\\# Liveness tomb_bits: {}
\\# Liveness Extra Data: {d} ({})
\\# Liveness special table: {d} ({})
\\
, .{
fmtIntSizeBin(total_bytes),
air.instructions.len, fmtIntSizeBin(instruction_bytes),
air.extra.len, fmtIntSizeBin(extra_bytes),
fmtIntSizeBin(tomb_bytes),
if (liveness) |l| l.extra.len else 0, fmtIntSizeBin(liveness_extra_bytes),
if (liveness) |l| l.special.count() else 0, fmtIntSizeBin(liveness_special_bytes),
}) catch return;
// zig fmt: on
var writer: Writer = .{
.module = module,
.gpa = module.gpa,
.air = air,
.liveness = liveness,
.indent = 2,
.skip_body = false,
};
writer.writeBody(stream, air.getMainBody()) catch return;
}
pub fn writeInst(
stream: anytype,
inst: Air.Inst.Index,
module: *Module,
air: Air,
liveness: ?Liveness,
) void {
var writer: Writer = .{
.module = module,
.gpa = module.gpa,
.air = air,
.liveness = liveness,
.indent = 2,
.skip_body = true,
};
writer.writeInst(stream, inst) catch return;
}
pub fn dump(module: *Module, air: Air, liveness: ?Liveness) void {
write(std.io.getStdErr().writer(), module, air, liveness);
}
pub fn dumpInst(inst: Air.Inst.Index, module: *Module, air: Air, liveness: ?Liveness) void {
writeInst(std.io.getStdErr().writer(), inst, module, air, liveness);
}
const Writer = struct {
module: *Module,
gpa: Allocator,
air: Air,
liveness: ?Liveness,
indent: usize,
skip_body: bool,
fn writeBody(w: *Writer, s: anytype, body: []const Air.Inst.Index) @TypeOf(s).Error!void {
for (body) |inst| {
try w.writeInst(s, inst);
try s.writeByte('\n');
}
}
fn writeInst(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const tag = w.air.instructions.items(.tag)[@intFromEnum(inst)];
try s.writeByteNTimes(' ', w.indent);
try s.print("%{d}{c}= {s}(", .{
@intFromEnum(inst),
@as(u8, if (if (w.liveness) |liveness| liveness.isUnused(inst) else false) '!' else ' '),
@tagName(tag),
});
switch (tag) {
.add,
.add_optimized,
.add_safe,
.add_wrap,
.add_sat,
.sub,
.sub_optimized,
.sub_safe,
.sub_wrap,
.sub_sat,
.mul,
.mul_optimized,
.mul_safe,
.mul_wrap,
.mul_sat,
.div_float,
.div_trunc,
.div_floor,
.div_exact,
.rem,
.mod,
.bit_and,
.bit_or,
.xor,
.cmp_lt,
.cmp_lte,
.cmp_eq,
.cmp_gte,
.cmp_gt,
.cmp_neq,
.bool_and,
.bool_or,
.store,
.store_safe,
.array_elem_val,
.slice_elem_val,
.ptr_elem_val,
.shl,
.shl_exact,
.shl_sat,
.shr,
.shr_exact,
.set_union_tag,
.min,
.max,
.div_float_optimized,
.div_trunc_optimized,
.div_floor_optimized,
.div_exact_optimized,
.rem_optimized,
.mod_optimized,
.cmp_lt_optimized,
.cmp_lte_optimized,
.cmp_eq_optimized,
.cmp_gte_optimized,
.cmp_gt_optimized,
.cmp_neq_optimized,
.memcpy,
.memset,
.memset_safe,
=> try w.writeBinOp(s, inst),
.is_null,
.is_non_null,
.is_null_ptr,
.is_non_null_ptr,
.is_err,
.is_non_err,
.is_err_ptr,
.is_non_err_ptr,
.int_from_ptr,
.int_from_bool,
.ret,
.ret_safe,
.ret_load,
.is_named_enum_value,
.tag_name,
.error_name,
.sqrt,
.sin,
.cos,
.tan,
.exp,
.exp2,
.log,
.log2,
.log10,
.floor,
.ceil,
.round,
.trunc_float,
.neg,
.neg_optimized,
.cmp_lt_errors_len,
.set_err_return_trace,
.c_va_end,
=> try w.writeUnOp(s, inst),
.trap,
.breakpoint,
.unreach,
.ret_addr,
.frame_addr,
.save_err_return_trace_index,
=> try w.writeNoOp(s, inst),
.alloc,
.ret_ptr,
.err_return_trace,
.c_va_start,
=> try w.writeTy(s, inst),
.arg => try w.writeArg(s, inst),
.not,
.bitcast,
.load,
.fptrunc,
.fpext,
.intcast,
.trunc,
.optional_payload,
.optional_payload_ptr,
.optional_payload_ptr_set,
.errunion_payload_ptr_set,
.wrap_optional,
.unwrap_errunion_payload,
.unwrap_errunion_err,
.unwrap_errunion_payload_ptr,
.unwrap_errunion_err_ptr,
.wrap_errunion_payload,
.wrap_errunion_err,
.slice_ptr,
.slice_len,
.ptr_slice_len_ptr,
.ptr_slice_ptr_ptr,
.struct_field_ptr_index_0,
.struct_field_ptr_index_1,
.struct_field_ptr_index_2,
.struct_field_ptr_index_3,
.array_to_slice,
.float_from_int,
.splat,
.int_from_float,
.int_from_float_optimized,
.get_union_tag,
.clz,
.ctz,
.popcount,
.byte_swap,
.bit_reverse,
.abs,
.error_set_has_value,
.addrspace_cast,
.c_va_arg,
.c_va_copy,
=> try w.writeTyOp(s, inst),
.block, .dbg_inline_block => try w.writeBlock(s, tag, inst),
.loop => try w.writeLoop(s, inst),
.slice,
.slice_elem_ptr,
.ptr_elem_ptr,
.ptr_add,
.ptr_sub,
.add_with_overflow,
.sub_with_overflow,
.mul_with_overflow,
.shl_with_overflow,
=> try w.writeTyPlBin(s, inst),
.call,
.call_always_tail,
.call_never_tail,
.call_never_inline,
=> try w.writeCall(s, inst),
.dbg_var_ptr,
.dbg_var_val,
=> try w.writeDbgVar(s, inst),
.struct_field_ptr => try w.writeStructField(s, inst),
.struct_field_val => try w.writeStructField(s, inst),
.inferred_alloc => @panic("TODO"),
.inferred_alloc_comptime => @panic("TODO"),
.assembly => try w.writeAssembly(s, inst),
.dbg_stmt => try w.writeDbgStmt(s, inst),
.aggregate_init => try w.writeAggregateInit(s, inst),
.union_init => try w.writeUnionInit(s, inst),
.br => try w.writeBr(s, inst),
.cond_br => try w.writeCondBr(s, inst),
.@"try" => try w.writeTry(s, inst),
.try_ptr => try w.writeTryPtr(s, inst),
.switch_br => try w.writeSwitchBr(s, inst),
.cmpxchg_weak, .cmpxchg_strong => try w.writeCmpxchg(s, inst),
.fence => try w.writeFence(s, inst),
.atomic_load => try w.writeAtomicLoad(s, inst),
.prefetch => try w.writePrefetch(s, inst),
.atomic_store_unordered => try w.writeAtomicStore(s, inst, .unordered),
.atomic_store_monotonic => try w.writeAtomicStore(s, inst, .monotonic),
.atomic_store_release => try w.writeAtomicStore(s, inst, .release),
.atomic_store_seq_cst => try w.writeAtomicStore(s, inst, .seq_cst),
.atomic_rmw => try w.writeAtomicRmw(s, inst),
.field_parent_ptr => try w.writeFieldParentPtr(s, inst),
.wasm_memory_size => try w.writeWasmMemorySize(s, inst),
.wasm_memory_grow => try w.writeWasmMemoryGrow(s, inst),
.mul_add => try w.writeMulAdd(s, inst),
.select => try w.writeSelect(s, inst),
.shuffle => try w.writeShuffle(s, inst),
.reduce, .reduce_optimized => try w.writeReduce(s, inst),
.cmp_vector, .cmp_vector_optimized => try w.writeCmpVector(s, inst),
.vector_store_elem => try w.writeVectorStoreElem(s, inst),
.work_item_id,
.work_group_size,
.work_group_id,
=> try w.writeWorkDimension(s, inst),
}
try s.writeByte(')');
}
fn writeBinOp(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const bin_op = w.air.instructions.items(.data)[@intFromEnum(inst)].bin_op;
try w.writeOperand(s, inst, 0, bin_op.lhs);
try s.writeAll(", ");
try w.writeOperand(s, inst, 1, bin_op.rhs);
}
fn writeUnOp(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const un_op = w.air.instructions.items(.data)[@intFromEnum(inst)].un_op;
try w.writeOperand(s, inst, 0, un_op);
}
fn writeNoOp(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
_ = w;
_ = inst;
// no-op, no argument to write
}
fn writeType(w: *Writer, s: anytype, ty: Type) !void {
return ty.print(s, w.module);
}
fn writeTy(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const ty = w.air.instructions.items(.data)[@intFromEnum(inst)].ty;
try w.writeType(s, ty);
}
fn writeArg(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const arg = w.air.instructions.items(.data)[@intFromEnum(inst)].arg;
try w.writeType(s, arg.ty.toType());
try s.print(", {d}", .{arg.src_index});
}
fn writeTyOp(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const ty_op = w.air.instructions.items(.data)[@intFromEnum(inst)].ty_op;
try w.writeType(s, ty_op.ty.toType());
try s.writeAll(", ");
try w.writeOperand(s, inst, 0, ty_op.operand);
}
fn writeBlock(w: *Writer, s: anytype, tag: Air.Inst.Tag, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const ty_pl = w.air.instructions.items(.data)[@intFromEnum(inst)].ty_pl;
try w.writeType(s, ty_pl.ty.toType());
const body: []const Air.Inst.Index = @ptrCast(switch (tag) {
inline .block, .dbg_inline_block => |comptime_tag| body: {
const extra = w.air.extraData(switch (comptime_tag) {
.block => Air.Block,
.dbg_inline_block => Air.DbgInlineBlock,
else => unreachable,
}, ty_pl.payload);
switch (comptime_tag) {
.block => {},
.dbg_inline_block => {
try s.writeAll(", ");
try w.writeInstRef(s, Air.internedToRef(extra.data.func), false);
},
else => unreachable,
}
break :body w.air.extra[extra.end..][0..extra.data.body_len];
},
else => unreachable,
});
if (w.skip_body) return s.writeAll(", ...");
const liveness_block = if (w.liveness) |liveness|
liveness.getBlock(inst)
else
Liveness.BlockSlices{ .deaths = &.{} };
try s.writeAll(", {\n");
const old_indent = w.indent;
w.indent += 2;
try w.writeBody(s, body);
w.indent = old_indent;
try s.writeByteNTimes(' ', w.indent);
try s.writeAll("}");
for (liveness_block.deaths) |operand| {
try s.print(" %{d}!", .{@intFromEnum(operand)});
}
}
fn writeLoop(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const ty_pl = w.air.instructions.items(.data)[@intFromEnum(inst)].ty_pl;
const extra = w.air.extraData(Air.Block, ty_pl.payload);
const body: []const Air.Inst.Index = @ptrCast(w.air.extra[extra.end..][0..extra.data.body_len]);
try w.writeType(s, ty_pl.ty.toType());
if (w.skip_body) return s.writeAll(", ...");
try s.writeAll(", {\n");
const old_indent = w.indent;
w.indent += 2;
try w.writeBody(s, body);
w.indent = old_indent;
try s.writeByteNTimes(' ', w.indent);
try s.writeAll("}");
}
fn writeAggregateInit(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const mod = w.module;
const ty_pl = w.air.instructions.items(.data)[@intFromEnum(inst)].ty_pl;
const vector_ty = ty_pl.ty.toType();
const len = @as(usize, @intCast(vector_ty.arrayLen(mod)));
const elements = @as([]const Air.Inst.Ref, @ptrCast(w.air.extra[ty_pl.payload..][0..len]));
try w.writeType(s, vector_ty);
try s.writeAll(", [");
for (elements, 0..) |elem, i| {
if (i != 0) try s.writeAll(", ");
try w.writeOperand(s, inst, i, elem);
}
try s.writeAll("]");
}
fn writeUnionInit(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const ty_pl = w.air.instructions.items(.data)[@intFromEnum(inst)].ty_pl;
const extra = w.air.extraData(Air.UnionInit, ty_pl.payload).data;
try s.print("{d}, ", .{extra.field_index});
try w.writeOperand(s, inst, 0, extra.init);
}
fn writeStructField(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const ty_pl = w.air.instructions.items(.data)[@intFromEnum(inst)].ty_pl;
const extra = w.air.extraData(Air.StructField, ty_pl.payload).data;
try w.writeOperand(s, inst, 0, extra.struct_operand);
try s.print(", {d}", .{extra.field_index});
}
fn writeTyPlBin(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const data = w.air.instructions.items(.data);
const ty_pl = data[@intFromEnum(inst)].ty_pl;
const extra = w.air.extraData(Air.Bin, ty_pl.payload).data;
const inst_ty = data[@intFromEnum(inst)].ty_pl.ty.toType();
try w.writeType(s, inst_ty);
try s.writeAll(", ");
try w.writeOperand(s, inst, 0, extra.lhs);
try s.writeAll(", ");
try w.writeOperand(s, inst, 1, extra.rhs);
}
fn writeCmpxchg(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const ty_pl = w.air.instructions.items(.data)[@intFromEnum(inst)].ty_pl;
const extra = w.air.extraData(Air.Cmpxchg, ty_pl.payload).data;
try w.writeOperand(s, inst, 0, extra.ptr);
try s.writeAll(", ");
try w.writeOperand(s, inst, 1, extra.expected_value);
try s.writeAll(", ");
try w.writeOperand(s, inst, 2, extra.new_value);
try s.print(", {s}, {s}", .{
@tagName(extra.successOrder()), @tagName(extra.failureOrder()),
});
}
fn writeMulAdd(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const pl_op = w.air.instructions.items(.data)[@intFromEnum(inst)].pl_op;
const extra = w.air.extraData(Air.Bin, pl_op.payload).data;
try w.writeOperand(s, inst, 0, extra.lhs);
try s.writeAll(", ");
try w.writeOperand(s, inst, 1, extra.rhs);
try s.writeAll(", ");
try w.writeOperand(s, inst, 2, pl_op.operand);
}
fn writeShuffle(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const ty_pl = w.air.instructions.items(.data)[@intFromEnum(inst)].ty_pl;
const extra = w.air.extraData(Air.Shuffle, ty_pl.payload).data;
try w.writeOperand(s, inst, 0, extra.a);
try s.writeAll(", ");
try w.writeOperand(s, inst, 1, extra.b);
try s.print(", mask {d}, len {d}", .{ extra.mask, extra.mask_len });
}
fn writeSelect(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const mod = w.module;
const pl_op = w.air.instructions.items(.data)[@intFromEnum(inst)].pl_op;
const extra = w.air.extraData(Air.Bin, pl_op.payload).data;
const elem_ty = w.typeOfIndex(inst).childType(mod);
try w.writeType(s, elem_ty);
try s.writeAll(", ");
try w.writeOperand(s, inst, 0, pl_op.operand);
try s.writeAll(", ");
try w.writeOperand(s, inst, 1, extra.lhs);
try s.writeAll(", ");
try w.writeOperand(s, inst, 2, extra.rhs);
}
fn writeReduce(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const reduce = w.air.instructions.items(.data)[@intFromEnum(inst)].reduce;
try w.writeOperand(s, inst, 0, reduce.operand);
try s.print(", {s}", .{@tagName(reduce.operation)});
}
fn writeCmpVector(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const ty_pl = w.air.instructions.items(.data)[@intFromEnum(inst)].ty_pl;
const extra = w.air.extraData(Air.VectorCmp, ty_pl.payload).data;
try s.print("{s}, ", .{@tagName(extra.compareOperator())});
try w.writeOperand(s, inst, 0, extra.lhs);
try s.writeAll(", ");
try w.writeOperand(s, inst, 1, extra.rhs);
}
fn writeVectorStoreElem(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const data = w.air.instructions.items(.data)[@intFromEnum(inst)].vector_store_elem;
const extra = w.air.extraData(Air.VectorCmp, data.payload).data;
try w.writeOperand(s, inst, 0, data.vector_ptr);
try s.writeAll(", ");
try w.writeOperand(s, inst, 1, extra.lhs);
try s.writeAll(", ");
try w.writeOperand(s, inst, 2, extra.rhs);
}
fn writeFence(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const atomic_order = w.air.instructions.items(.data)[@intFromEnum(inst)].fence;
try s.print("{s}", .{@tagName(atomic_order)});
}
fn writeAtomicLoad(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const atomic_load = w.air.instructions.items(.data)[@intFromEnum(inst)].atomic_load;
try w.writeOperand(s, inst, 0, atomic_load.ptr);
try s.print(", {s}", .{@tagName(atomic_load.order)});
}
fn writePrefetch(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const prefetch = w.air.instructions.items(.data)[@intFromEnum(inst)].prefetch;
try w.writeOperand(s, inst, 0, prefetch.ptr);
try s.print(", {s}, {d}, {s}", .{
@tagName(prefetch.rw), prefetch.locality, @tagName(prefetch.cache),
});
}
fn writeAtomicStore(
w: *Writer,
s: anytype,
inst: Air.Inst.Index,
order: std.builtin.AtomicOrder,
) @TypeOf(s).Error!void {
const bin_op = w.air.instructions.items(.data)[@intFromEnum(inst)].bin_op;
try w.writeOperand(s, inst, 0, bin_op.lhs);
try s.writeAll(", ");
try w.writeOperand(s, inst, 1, bin_op.rhs);
try s.print(", {s}", .{@tagName(order)});
}
fn writeAtomicRmw(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const pl_op = w.air.instructions.items(.data)[@intFromEnum(inst)].pl_op;
const extra = w.air.extraData(Air.AtomicRmw, pl_op.payload).data;
try w.writeOperand(s, inst, 0, pl_op.operand);
try s.writeAll(", ");
try w.writeOperand(s, inst, 1, extra.operand);
try s.print(", {s}, {s}", .{ @tagName(extra.op()), @tagName(extra.ordering()) });
}
fn writeFieldParentPtr(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const ty_pl = w.air.instructions.items(.data)[@intFromEnum(inst)].ty_pl;
const extra = w.air.extraData(Air.FieldParentPtr, ty_pl.payload).data;
try w.writeOperand(s, inst, 0, extra.field_ptr);
try s.print(", {d}", .{extra.field_index});
}
fn writeAssembly(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const ty_pl = w.air.instructions.items(.data)[@intFromEnum(inst)].ty_pl;
const extra = w.air.extraData(Air.Asm, ty_pl.payload);
const is_volatile = @as(u1, @truncate(extra.data.flags >> 31)) != 0;
const clobbers_len = @as(u31, @truncate(extra.data.flags));
var extra_i: usize = extra.end;
var op_index: usize = 0;
const ret_ty = w.typeOfIndex(inst);
try w.writeType(s, ret_ty);
if (is_volatile) {
try s.writeAll(", volatile");
}
const outputs = @as([]const Air.Inst.Ref, @ptrCast(w.air.extra[extra_i..][0..extra.data.outputs_len]));
extra_i += outputs.len;
const inputs = @as([]const Air.Inst.Ref, @ptrCast(w.air.extra[extra_i..][0..extra.data.inputs_len]));
extra_i += inputs.len;
for (outputs) |output| {
const extra_bytes = std.mem.sliceAsBytes(w.air.extra[extra_i..]);
const constraint = std.mem.sliceTo(extra_bytes, 0);
const name = std.mem.sliceTo(extra_bytes[constraint.len + 1 ..], 0);
// This equation accounts for the fact that even if we have exactly 4 bytes
// for the strings and their null terminators, we still use the next u32
// for the null terminator.
extra_i += (constraint.len + name.len + (2 + 3)) / 4;
if (output == .none) {
try s.print(", [{s}] -> {s}", .{ name, constraint });
} else {
try s.print(", [{s}] out {s} = (", .{ name, constraint });
try w.writeOperand(s, inst, op_index, output);
op_index += 1;
try s.writeByte(')');
}
}
for (inputs) |input| {
const extra_bytes = std.mem.sliceAsBytes(w.air.extra[extra_i..]);
const constraint = std.mem.sliceTo(extra_bytes, 0);
const name = std.mem.sliceTo(extra_bytes[constraint.len + 1 ..], 0);
// This equation accounts for the fact that even if we have exactly 4 bytes
// for the strings and their null terminators, we still use the next u32
// for the null terminator.
extra_i += (constraint.len + name.len + 1) / 4 + 1;
try s.print(", [{s}] in {s} = (", .{ name, constraint });
try w.writeOperand(s, inst, op_index, input);
op_index += 1;
try s.writeByte(')');
}
{
var clobber_i: u32 = 0;
while (clobber_i < clobbers_len) : (clobber_i += 1) {
const extra_bytes = std.mem.sliceAsBytes(w.air.extra[extra_i..]);
const clobber = std.mem.sliceTo(extra_bytes, 0);
// This equation accounts for the fact that even if we have exactly 4 bytes
// for the string, we still use the next u32 for the null terminator.
extra_i += clobber.len / 4 + 1;
try s.writeAll(", ~{");
try s.writeAll(clobber);
try s.writeAll("}");
}
}
const asm_source = std.mem.sliceAsBytes(w.air.extra[extra_i..])[0..extra.data.source_len];
try s.print(", \"{s}\"", .{asm_source});
}
fn writeDbgStmt(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const dbg_stmt = w.air.instructions.items(.data)[@intFromEnum(inst)].dbg_stmt;
try s.print("{d}:{d}", .{ dbg_stmt.line + 1, dbg_stmt.column + 1 });
}
fn writeDbgVar(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const pl_op = w.air.instructions.items(.data)[@intFromEnum(inst)].pl_op;
try w.writeOperand(s, inst, 0, pl_op.operand);
const name = w.air.nullTerminatedString(pl_op.payload);
try s.print(", \"{}\"", .{std.zig.fmtEscapes(name)});
}
fn writeCall(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const pl_op = w.air.instructions.items(.data)[@intFromEnum(inst)].pl_op;
const extra = w.air.extraData(Air.Call, pl_op.payload);
const args = @as([]const Air.Inst.Ref, @ptrCast(w.air.extra[extra.end..][0..extra.data.args_len]));
try w.writeOperand(s, inst, 0, pl_op.operand);
try s.writeAll(", [");
for (args, 0..) |arg, i| {
if (i != 0) try s.writeAll(", ");
try w.writeOperand(s, inst, 1 + i, arg);
}
try s.writeAll("]");
}
fn writeBr(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const br = w.air.instructions.items(.data)[@intFromEnum(inst)].br;
try w.writeInstIndex(s, br.block_inst, false);
try s.writeAll(", ");
try w.writeOperand(s, inst, 0, br.operand);
}
fn writeTry(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const pl_op = w.air.instructions.items(.data)[@intFromEnum(inst)].pl_op;
const extra = w.air.extraData(Air.Try, pl_op.payload);
const body: []const Air.Inst.Index = @ptrCast(w.air.extra[extra.end..][0..extra.data.body_len]);
const liveness_condbr = if (w.liveness) |liveness|
liveness.getCondBr(inst)
else
Liveness.CondBrSlices{ .then_deaths = &.{}, .else_deaths = &.{} };
try w.writeOperand(s, inst, 0, pl_op.operand);
if (w.skip_body) return s.writeAll(", ...");
try s.writeAll(", {\n");
const old_indent = w.indent;
w.indent += 2;
if (liveness_condbr.else_deaths.len != 0) {
try s.writeByteNTimes(' ', w.indent);
for (liveness_condbr.else_deaths, 0..) |operand, i| {
if (i != 0) try s.writeAll(" ");
try s.print("%{d}!", .{@intFromEnum(operand)});
}
try s.writeAll("\n");
}
try w.writeBody(s, body);
w.indent = old_indent;
try s.writeByteNTimes(' ', w.indent);
try s.writeAll("}");
for (liveness_condbr.then_deaths) |operand| {
try s.print(" %{d}!", .{@intFromEnum(operand)});
}
}
fn writeTryPtr(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const ty_pl = w.air.instructions.items(.data)[@intFromEnum(inst)].ty_pl;
const extra = w.air.extraData(Air.TryPtr, ty_pl.payload);
const body: []const Air.Inst.Index = @ptrCast(w.air.extra[extra.end..][0..extra.data.body_len]);
const liveness_condbr = if (w.liveness) |liveness|
liveness.getCondBr(inst)
else
Liveness.CondBrSlices{ .then_deaths = &.{}, .else_deaths = &.{} };
try w.writeOperand(s, inst, 0, extra.data.ptr);
try s.writeAll(", ");
try w.writeType(s, ty_pl.ty.toType());
if (w.skip_body) return s.writeAll(", ...");
try s.writeAll(", {\n");
const old_indent = w.indent;
w.indent += 2;
if (liveness_condbr.else_deaths.len != 0) {
try s.writeByteNTimes(' ', w.indent);
for (liveness_condbr.else_deaths, 0..) |operand, i| {
if (i != 0) try s.writeAll(" ");
try s.print("%{d}!", .{@intFromEnum(operand)});
}
try s.writeAll("\n");
}
try w.writeBody(s, body);
w.indent = old_indent;
try s.writeByteNTimes(' ', w.indent);
try s.writeAll("}");
for (liveness_condbr.then_deaths) |operand| {
try s.print(" %{d}!", .{@intFromEnum(operand)});
}
}
fn writeCondBr(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const pl_op = w.air.instructions.items(.data)[@intFromEnum(inst)].pl_op;
const extra = w.air.extraData(Air.CondBr, pl_op.payload);
const then_body: []const Air.Inst.Index = @ptrCast(w.air.extra[extra.end..][0..extra.data.then_body_len]);
const else_body: []const Air.Inst.Index = @ptrCast(w.air.extra[extra.end + then_body.len ..][0..extra.data.else_body_len]);
const liveness_condbr = if (w.liveness) |liveness|
liveness.getCondBr(inst)
else
Liveness.CondBrSlices{ .then_deaths = &.{}, .else_deaths = &.{} };
try w.writeOperand(s, inst, 0, pl_op.operand);
if (w.skip_body) return s.writeAll(", ...");
try s.writeAll(", {\n");
const old_indent = w.indent;
w.indent += 2;
if (liveness_condbr.then_deaths.len != 0) {
try s.writeByteNTimes(' ', w.indent);
for (liveness_condbr.then_deaths, 0..) |operand, i| {
if (i != 0) try s.writeAll(" ");
try s.print("%{d}!", .{@intFromEnum(operand)});
}
try s.writeAll("\n");
}
try w.writeBody(s, then_body);
try s.writeByteNTimes(' ', old_indent);
try s.writeAll("}, {\n");
if (liveness_condbr.else_deaths.len != 0) {
try s.writeByteNTimes(' ', w.indent);
for (liveness_condbr.else_deaths, 0..) |operand, i| {
if (i != 0) try s.writeAll(" ");
try s.print("%{d}!", .{@intFromEnum(operand)});
}
try s.writeAll("\n");
}
try w.writeBody(s, else_body);
w.indent = old_indent;
try s.writeByteNTimes(' ', old_indent);
try s.writeAll("}");
}
fn writeSwitchBr(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const pl_op = w.air.instructions.items(.data)[@intFromEnum(inst)].pl_op;
const switch_br = w.air.extraData(Air.SwitchBr, pl_op.payload);
const liveness = if (w.liveness) |liveness|
liveness.getSwitchBr(w.gpa, inst, switch_br.data.cases_len + 1) catch
@panic("out of memory")
else blk: {
const slice = w.gpa.alloc([]const Air.Inst.Index, switch_br.data.cases_len + 1) catch
@panic("out of memory");
@memset(slice, &.{});
break :blk Liveness.SwitchBrTable{ .deaths = slice };
};
defer w.gpa.free(liveness.deaths);
var extra_index: usize = switch_br.end;
var case_i: u32 = 0;
try w.writeOperand(s, inst, 0, pl_op.operand);
if (w.skip_body) return s.writeAll(", ...");
const old_indent = w.indent;
w.indent += 2;
while (case_i < switch_br.data.cases_len) : (case_i += 1) {
const case = w.air.extraData(Air.SwitchBr.Case, extra_index);
const items = @as([]const Air.Inst.Ref, @ptrCast(w.air.extra[case.end..][0..case.data.items_len]));
const case_body: []const Air.Inst.Index = @ptrCast(w.air.extra[case.end + items.len ..][0..case.data.body_len]);
extra_index = case.end + case.data.items_len + case_body.len;
try s.writeAll(", [");
for (items, 0..) |item, item_i| {
if (item_i != 0) try s.writeAll(", ");
try w.writeInstRef(s, item, false);
}
try s.writeAll("] => {\n");
w.indent += 2;
const deaths = liveness.deaths[case_i];
if (deaths.len != 0) {
try s.writeByteNTimes(' ', w.indent);
for (deaths, 0..) |operand, i| {
if (i != 0) try s.writeAll(" ");
try s.print("%{d}!", .{@intFromEnum(operand)});
}
try s.writeAll("\n");
}
try w.writeBody(s, case_body);
w.indent -= 2;
try s.writeByteNTimes(' ', w.indent);
try s.writeAll("}");
}
const else_body: []const Air.Inst.Index = @ptrCast(w.air.extra[extra_index..][0..switch_br.data.else_body_len]);
if (else_body.len != 0) {
try s.writeAll(", else => {\n");
w.indent += 2;
const deaths = liveness.deaths[liveness.deaths.len - 1];
if (deaths.len != 0) {
try s.writeByteNTimes(' ', w.indent);
for (deaths, 0..) |operand, i| {
if (i != 0) try s.writeAll(" ");
try s.print("%{d}!", .{@intFromEnum(operand)});
}
try s.writeAll("\n");
}
try w.writeBody(s, else_body);
w.indent -= 2;
try s.writeByteNTimes(' ', w.indent);
try s.writeAll("}");
}
try s.writeAll("\n");
try s.writeByteNTimes(' ', old_indent);
}
fn writeWasmMemorySize(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const pl_op = w.air.instructions.items(.data)[@intFromEnum(inst)].pl_op;
try s.print("{d}", .{pl_op.payload});
}
fn writeWasmMemoryGrow(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const pl_op = w.air.instructions.items(.data)[@intFromEnum(inst)].pl_op;
try s.print("{d}, ", .{pl_op.payload});
try w.writeOperand(s, inst, 0, pl_op.operand);
}
fn writeWorkDimension(w: *Writer, s: anytype, inst: Air.Inst.Index) @TypeOf(s).Error!void {
const pl_op = w.air.instructions.items(.data)[@intFromEnum(inst)].pl_op;
try s.print("{d}", .{pl_op.payload});
}
fn writeOperand(
w: *Writer,
s: anytype,
inst: Air.Inst.Index,
op_index: usize,
operand: Air.Inst.Ref,
) @TypeOf(s).Error!void {
const small_tomb_bits = Liveness.bpi - 1;
const dies = if (w.liveness) |liveness| blk: {
if (op_index < small_tomb_bits)
break :blk liveness.operandDies(inst, @as(Liveness.OperandInt, @intCast(op_index)));
var extra_index = liveness.special.get(inst).?;
var tomb_op_index: usize = small_tomb_bits;
while (true) {
const bits = liveness.extra[extra_index];
if (op_index < tomb_op_index + 31) {
break :blk @as(u1, @truncate(bits >> @as(u5, @intCast(op_index - tomb_op_index)))) != 0;
}
if ((bits >> 31) != 0) break :blk false;
extra_index += 1;
tomb_op_index += 31;
}
} else false;
return w.writeInstRef(s, operand, dies);
}
fn writeInstRef(
w: *Writer,
s: anytype,
operand: Air.Inst.Ref,
dies: bool,
) @TypeOf(s).Error!void {
if (@intFromEnum(operand) < InternPool.static_len) {
return s.print("@{}", .{operand});
} else if (operand.toInterned()) |ip_index| {
const mod = w.module;
const ty = Type.fromInterned(mod.intern_pool.indexToKey(ip_index).typeOf());
try s.print("<{}, {}>", .{
ty.fmt(mod),
Value.fromInterned(ip_index).fmtValue(mod, null),
});
} else {
return w.writeInstIndex(s, operand.toIndex().?, dies);
}
}
fn writeInstIndex(
w: *Writer,
s: anytype,
inst: Air.Inst.Index,
dies: bool,
) @TypeOf(s).Error!void {
_ = w;
try s.print("%{d}", .{@intFromEnum(inst)});
if (dies) try s.writeByte('!');
}
fn typeOfIndex(w: *Writer, inst: Air.Inst.Index) Type {
const mod = w.module;
return w.air.typeOfIndex(inst, &mod.intern_pool);
}
};