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stage2: make AIR not reference ZIR for inline assembly

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Instead it stores all the information it needs to into AIR.

closes #10784
This commit is contained in:
Andrew Kelley
2022-02-18 19:41:32 -07:00
parent 123076ea88
commit 4e1e5ab622
11 changed files with 505 additions and 350 deletions
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95
src/codegen/c.zig
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@@ -15,7 +15,6 @@ const Decl = Module.Decl;
const trace = @import("../tracy.zig").trace;
const LazySrcLoc = Module.LazySrcLoc;
const Air = @import("../Air.zig");
const Zir = @import("../Zir.zig");
const Liveness = @import("../Liveness.zig");
const Mutability = enum { Const, Mut };
@@ -2805,49 +2804,48 @@ fn airSwitchBr(f: *Function, inst: Air.Inst.Index) !CValue {
}
fn airAsm(f: *Function, inst: Air.Inst.Index) !CValue {
const air_datas = f.air.instructions.items(.data);
const air_extra = f.air.extraData(Air.Asm, air_datas[inst].ty_pl.payload);
const zir = f.object.dg.decl.getFileScope().zir;
const extended = zir.instructions.items(.data)[air_extra.data.zir_index].extended;
const zir_extra = zir.extraData(Zir.Inst.Asm, extended.operand);
const asm_source = zir.nullTerminatedString(zir_extra.data.asm_source);
const outputs_len = @truncate(u5, extended.small);
const args_len = @truncate(u5, extended.small >> 5);
const clobbers_len = @truncate(u5, extended.small >> 10);
_ = clobbers_len; // TODO honor these
const is_volatile = @truncate(u1, extended.small >> 15) != 0;
const outputs = @bitCast([]const Air.Inst.Ref, f.air.extra[air_extra.end..][0..outputs_len]);
const args = @bitCast([]const Air.Inst.Ref, f.air.extra[air_extra.end + outputs.len ..][0..args_len]);
const ty_pl = f.air.instructions.items(.data)[inst].ty_pl;
const extra = f.air.extraData(Air.Asm, ty_pl.payload);
const is_volatile = @truncate(u1, extra.data.flags >> 31) != 0;
const clobbers_len = @truncate(u31, extra.data.flags);
var extra_i: usize = extra.end;
const outputs = @bitCast([]const Air.Inst.Ref, f.air.extra[extra_i..][0..extra.data.outputs_len]);
extra_i += outputs.len;
const inputs = @bitCast([]const Air.Inst.Ref, f.air.extra[extra_i..][0..extra.data.inputs_len]);
extra_i += inputs.len;
if (outputs_len > 1) {
if (!is_volatile and f.liveness.isUnused(inst)) return CValue.none;
if (outputs.len > 1) {
return f.fail("TODO implement codegen for asm with more than 1 output", .{});
}
if (f.liveness.isUnused(inst) and !is_volatile)
return CValue.none;
var extra_i: usize = zir_extra.end;
const output_constraint: ?[]const u8 = out: {
var i: usize = 0;
while (i < outputs_len) : (i += 1) {
const output = zir.extraData(Zir.Inst.Asm.Output, extra_i);
extra_i = output.end;
break :out zir.nullTerminatedString(output.data.constraint);
const output_constraint: ?[]const u8 = for (outputs) |output| {
if (output != .none) {
return f.fail("TODO implement codegen for non-expr asm", .{});
}
break :out null;
};
const args_extra_begin = extra_i;
const constraint = std.mem.sliceTo(std.mem.sliceAsBytes(f.air.extra[extra_i..]), 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 += constraint.len / 4 + 1;
break constraint;
} else null;
const writer = f.object.writer();
for (args) |arg| {
const input = zir.extraData(Zir.Inst.Asm.Input, extra_i);
extra_i = input.end;
const constraint = zir.nullTerminatedString(input.data.constraint);
const inputs_extra_begin = extra_i;
for (inputs) |input| {
const constraint = std.mem.sliceTo(std.mem.sliceAsBytes(f.air.extra[extra_i..]), 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 += constraint.len / 4 + 1;
if (constraint[0] == '{' and constraint[constraint.len - 1] == '}') {
const reg = constraint[1 .. constraint.len - 1];
const arg_c_value = try f.resolveInst(arg);
const arg_c_value = try f.resolveInst(input);
try writer.writeAll("register ");
try f.renderType(writer, f.air.typeOf(arg));
try f.renderType(writer, f.air.typeOf(input));
try writer.print(" {s}_constant __asm__(\"{s}\") = ", .{ reg, reg });
try f.writeCValue(writer, arg_c_value);
@@ -2856,21 +2854,38 @@ fn airAsm(f: *Function, inst: Air.Inst.Index) !CValue {
return f.fail("TODO non-explicit inline asm regs", .{});
}
}
{
var clobber_i: u32 = 0;
while (clobber_i < clobbers_len) : (clobber_i += 1) {
const clobber = std.mem.sliceTo(std.mem.sliceAsBytes(f.air.extra[extra_i..]), 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;
// TODO honor these
}
}
const asm_source = std.mem.sliceAsBytes(f.air.extra[extra_i..])[0..extra.data.source_len];
const volatile_string: []const u8 = if (is_volatile) "volatile " else "";
try writer.print("__asm {s}(\"{s}\"", .{ volatile_string, asm_source });
if (output_constraint) |_| {
return f.fail("TODO: CBE inline asm output", .{});
}
if (args.len > 0) {
if (inputs.len > 0) {
if (output_constraint == null) {
try writer.writeAll(" :");
}
try writer.writeAll(": ");
extra_i = args_extra_begin;
for (args) |_, index| {
const input = zir.extraData(Zir.Inst.Asm.Input, extra_i);
extra_i = input.end;
const constraint = zir.nullTerminatedString(input.data.constraint);
extra_i = inputs_extra_begin;
for (inputs) |_, index| {
const constraint = std.mem.sliceTo(std.mem.sliceAsBytes(f.air.extra[extra_i..]), 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 += constraint.len / 4 + 1;
if (constraint[0] == '{' and constraint[constraint.len - 1] == '}') {
const reg = constraint[1 .. constraint.len - 1];
if (index > 0) {