mirror/zig
1
0
Fork 0
mirror of https://github.com/ziglang/zig.git synced 2026-02-12 20:37:54 +00:00
Code Issues Packages Projects Releases Wiki Activity

wasm: implement @byteSwap for 16/32bit integers

Browse Source
This commit is contained in:
Luuk de Gram 2022-06-06 21:20:51 +02:00
parent c1eb6c30e8
commit bc499de328
1 changed files with 48 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

49
src/arch/wasm/CodeGen.zig
View File

@ -1541,6 +1541,7 @@ fn genInst(self: *Self, inst: Air.Inst.Index) !WValue {
.union_init => self.airUnionInit(inst),
.prefetch => self.airPrefetch(inst),
.popcount => self.airPopcount(inst),
.byte_swap => self.airByteSwap(inst),
.slice => self.airSlice(inst),
.slice_len => self.airSliceLen(inst),
@ -1590,7 +1591,6 @@ fn genInst(self: *Self, inst: Air.Inst.Index) !WValue {
.shl_sat,
.ret_addr,
.frame_addr,
.byte_swap,
.bit_reverse,
.is_err_ptr,
.is_non_err_ptr,
@ -4691,3 +4691,50 @@ fn lowerTry(
}
return self.load(err_union, pl_ty, pl_offset);
}
fn airByteSwap(self: *Self, inst: Air.Inst.Index) InnerError!WValue {
if (self.liveness.isUnused(inst)) {
return WValue{ .none = {} };
}
const ty_op = self.air.instructions.items(.data)[inst].ty_op;
const ty = self.air.typeOfIndex(inst);
const operand = try self.resolveInst(ty_op.operand);
if (ty.zigTypeTag() == .Vector) {
return self.fail("TODO: @byteSwap for vectors", .{});
}
const int_info = ty.intInfo(self.target);
// bytes are no-op
if (int_info.bits == 8) {
return operand;
}
switch (int_info.bits) {
16 => {
const shl_res = try self.binOp(operand, .{ .imm32 = 8 }, ty, .shl);
const tmp = try self.binOp(operand, .{ .imm32 = 0xFF00 }, ty, .@"and");
const shr_res = try self.binOp(tmp, .{ .imm32 = 8 }, ty, .shr);
const res = if (int_info.signedness == .signed) blk: {
break :blk try self.wrapOperand(shr_res, Type.u8);
} else shr_res;
return self.binOp(shl_res, res, ty, .@"or");
},
32 => {
const shl_tmp = try self.binOp(operand, .{ .imm32 = 8 }, ty, .shl);
const lhs = try self.binOp(shl_tmp, .{ .imm32 = 0xFF00FF00 }, ty, .@"and");
const shr_tmp = try self.binOp(operand, .{ .imm32 = 8 }, ty, .shr);
const rhs = try self.binOp(shr_tmp, .{ .imm32 = 0xFF00FF }, ty, .@"and");
const tmp_or = try self.binOp(lhs, rhs, ty, .@"or");
const shl = try self.binOp(tmp_or, .{ .imm32 = 16 }, ty, .shl);
const shr = try self.binOp(tmp_or, .{ .imm32 = 16 }, ty, .shr);
const res = if (int_info.signedness == .signed) blk: {
break :blk try self.wrapOperand(shr, Type.u16);
} else shr;
return self.binOp(shl, res, ty, .@"or");
},
else => return self.fail("TODO: @byteSwap for integers with bitsize {d}", .{int_info.bits}),
}
}