| """Developer API of IR node builder make function.""" |
| from __future__ import absolute_import as _abs |
| |
| from . import api as _api |
| from . import stmt as _stmt |
| from . import expr as _expr |
| from . import make as _make |
| from . import ir_pass as _pass |
| from . import container as _container |
| from ._ffi.base import string_types |
| from ._ffi.node import NodeGeneric |
| from ._ffi.runtime_ctypes import TVMType |
| from .expr import Call as _Call |
| |
| class WithScope(object): |
| """Auxiliary scope with""" |
| def __init__(self, enter_value, exit_cb): |
| self._enter_value = enter_value |
| self._exit_cb = exit_cb |
| |
| def __enter__(self): |
| return self._enter_value |
| |
| def __exit__(self, ptype, value, trace): |
| self._exit_cb() |
| |
| |
| class BufferVar(NodeGeneric): |
| """Buffer variable with content type, makes load store easily. |
| |
| Do not create it directly, create use IRBuilder. |
| |
| Examples |
| -------- |
| In the follow example, x is BufferVar. |
| :code:`x[0] = ...` directly emit a store to the IRBuilder, |
| :code:`x[10]` translates to Load. |
| |
| .. code-block:: python |
| |
| # The following code generate IR for x[0] = x[ |
| ib = tvm.ir_builder.create() |
| x = ib.pointer("float32") |
| x[0] = x[10] + 1 |
| |
| See Also |
| -------- |
| IRBuilder.pointer |
| IRBuilder.buffer_ptr |
| IRBuilder.allocate |
| """ |
| def __init__(self, builder, buffer_var, content_type): |
| self._builder = builder |
| self._buffer_var = buffer_var |
| self._content_type = content_type |
| |
| def asnode(self): |
| return self._buffer_var |
| |
| @property |
| def dtype(self): |
| return self._content_type |
| |
| def __getitem__(self, index): |
| t = TVMType(self._content_type) |
| if t.lanes > 1: |
| index = _make.Ramp(index * t.lanes, 1, t.lanes) |
| return _make.Load(self._content_type, self._buffer_var, index) |
| |
| def __setitem__(self, index, value): |
| value = _api.convert(value) |
| if value.dtype != self._content_type: |
| raise ValueError( |
| "data type does not match content type %s vs %s" % ( |
| value.dtype, self._content_type)) |
| t = TVMType(self._content_type) |
| if t.lanes > 1: |
| index = _make.Ramp(index * t.lanes, 1, t.lanes) |
| self._builder.emit(_make.Store(self._buffer_var, value, index)) |
| |
| |
| class IRBuilder(object): |
| """Auxiliary builder to build IR for testing and dev. |
| |
| Examples |
| -------- |
| .. code-block:: python |
| |
| ib = tvm.ir_builder.create() |
| n = tvm.var("n") |
| A = ib.allocate("float32", n, name="A") |
| with ib.for_range(0, n, name="i") as i: |
| with ib.if_scope((i % 2) == 0): |
| A[i] = A[i] + 1 |
| # The result stmt. |
| stmt = ib.get() |
| """ |
| def __init__(self): |
| self._seq_stack = [[]] |
| self.nidx = 0 |
| |
| def _pop_seq(self): |
| """Pop sequence from stack""" |
| seq = self._seq_stack.pop() |
| if not seq or callable(seq[-1]): |
| seq.append(_make.Evaluate(0)) |
| stmt = seq[-1] |
| for s in reversed(seq[:-1]): |
| if callable(s): |
| stmt = s(stmt) |
| else: |
| assert isinstance(s, _stmt.Stmt) |
| stmt = _make.Block(s, stmt) |
| return stmt |
| |
| def emit(self, stmt): |
| """Emit a statement to the end of current scope. |
| |
| Parameters |
| ---------- |
| stmt : Stmt or callable. |
| The statement to be emitted or callable that build stmt given body. |
| """ |
| if isinstance(stmt, _expr.Call): |
| stmt = _make.Evaluate(stmt) |
| assert isinstance(stmt, _stmt.Stmt) or callable(stmt) |
| self._seq_stack[-1].append(stmt) |
| |
| def scope_attr(self, node, attr_key, value): |
| """Create an AttrStmt at current scope. |
| |
| Parameters |
| ---------- |
| attr_key : str |
| The key of the attribute type. |
| |
| node : Node |
| The attribute node to annottate on. |
| |
| value : Expr |
| Attribute value. |
| |
| Examples |
| -------- |
| .. code-block:: python |
| |
| ib = tvm.ir_builder.create() |
| i = tvm.var("i") |
| x = ib.pointer("float32") |
| ib.scope_attr(x, "storage_scope", "global") |
| x[i] = x[i - 1] + 1 |
| """ |
| if isinstance(node, string_types): |
| node = _make.StringImm(node) |
| if isinstance(value, string_types): |
| value = _make.StringImm(value) |
| self.emit(lambda x: _make.AttrStmt(node, attr_key, value, x)) |
| |
| def for_range(self, begin, end, name="i", dtype="int32", for_type="serial"): |
| """Create a for iteration scope. |
| |
| Parameters |
| ---------- |
| begin : Expr |
| The min iteration scope. |
| |
| end : Expr |
| The end iteration scope |
| |
| name : str, optional |
| The name of iteration variable, if no input names, |
| using typical index names i, j, k, then i_nidx |
| |
| dtype : str, optional |
| The data type of iteration variable. |
| |
| for_type : str, optional |
| The special tag on the for loop. |
| |
| Returns |
| ------- |
| loop_scope : With.Scope of Var |
| The for scope, when enters returns loop_var |
| |
| Examples |
| -------- |
| .. code-block:: python |
| |
| ib = tvm.ir_builder.create() |
| x = ib.pointer("float32") |
| with ib.for_range(1, 10, name="i") as i: |
| x[i] = x[i - 1] + 1 |
| """ |
| if name == 'i': |
| name = chr(ord(name) + self.nidx) if self.nidx < 3 else name + "_" + str(self.nidx - 3) |
| self.nidx += 1 |
| self._seq_stack.append([]) |
| loop_var = _api.var(name, dtype=dtype) |
| extent = end if begin == 0 else _pass.Simplify(end - begin) |
| def _exit_cb(): |
| if for_type == "serial": |
| for_type_id = 0 |
| elif for_type == "parallel": |
| for_type_id = 1 |
| elif for_type == "vectorize": |
| for_type_id = 2 |
| elif for_type == "unroll": |
| for_type_id = 3 |
| else: |
| raise ValueError("Unknown for_type") |
| self.emit(_make.For( |
| loop_var, begin, extent, for_type_id, 0, self._pop_seq())) |
| return WithScope(loop_var, _exit_cb) |
| |
| def if_scope(self, cond): |
| """Create an if scope. |
| |
| Parameters |
| ---------- |
| cond : Expr |
| The condition. |
| |
| Returns |
| ------- |
| if_scope : WithScope |
| The result if scope. |
| |
| Examples |
| -------- |
| .. code-block:: python |
| |
| ib = tvm.ir_builder.create() |
| i = tvm.var("i") |
| x = ib.pointer("float32") |
| with ib.if_scope((i % 2) == 0): |
| x[i] = x[i - 1] + 1 |
| """ |
| self._seq_stack.append([]) |
| def _exit_cb(): |
| self.emit(_make.IfThenElse(cond, self._pop_seq(), None)) |
| return WithScope(None, _exit_cb) |
| |
| def else_scope(self): |
| """Create an else scope. |
| |
| This can only be used right after an if scope. |
| |
| Returns |
| ------- |
| else_scope : WithScope |
| The result else scope. |
| |
| Examples |
| -------- |
| .. code-block:: python |
| |
| ib = tvm.ir_builder.create() |
| i = tvm.var("i") |
| x = ib.pointer("float32") |
| with ib.if_scope((i % 2) == 0): |
| x[i] = x[i - 1] + 1 |
| with ib.else_scope(): |
| x[i] = x[i - 1] + 2 |
| """ |
| if not self._seq_stack[-1]: |
| raise RuntimeError("else_scope can only follow an if_scope") |
| prev = self._seq_stack[-1][-1] |
| if not isinstance(prev, _stmt.IfThenElse) or prev.else_case: |
| raise RuntimeError("else_scope can only follow an if_scope") |
| self._seq_stack[-1].pop() |
| self._seq_stack.append([]) |
| def _exit_cb(): |
| self.emit(_make.IfThenElse(prev.condition, prev.then_case, self._pop_seq())) |
| return WithScope(None, _exit_cb) |
| |
| def new_scope(self): |
| """Create new scope, |
| |
| this is useful to set boundary of attr and allocate. |
| |
| Returns |
| ------- |
| new_scope : WithScope |
| The result new scope. |
| """ |
| self._seq_stack.append([]) |
| def _exit_cb(): |
| self.emit(self._pop_seq()) |
| return WithScope(None, _exit_cb) |
| |
| def allocate(self, dtype, shape, name="buf", scope=None): |
| """Create a allocate statement. |
| |
| Parameters |
| ---------- |
| dtype : str |
| The content data type. |
| |
| shape : tuple of Expr |
| The shape of array to be allocated. |
| |
| name : str, optional |
| The name of the buffer. |
| |
| scope : str, optional |
| The scope of the buffer. |
| |
| Returns |
| ------- |
| buffer : BufferVar |
| The buffer var representing the buffer. |
| """ |
| buffer_var = _api.var(name, dtype="handle") |
| if not isinstance(shape, (list, tuple, _container.Array)): |
| shape = [shape] |
| if scope: |
| self.scope_attr(buffer_var, "storage_scope", scope) |
| self.emit(lambda x: _make.Allocate( |
| buffer_var, dtype, shape, _api.const(1, dtype="uint1"), x)) |
| return BufferVar(self, buffer_var, dtype) |
| |
| def pointer(self, content_type, name="ptr"): |
| """Create pointer variable with content type. |
| |
| Parameters |
| ---------- |
| content_type : str |
| The content data type. |
| |
| name : str, optional |
| The name of the pointer. |
| |
| Returns |
| ------- |
| ptr : BufferVar |
| The buffer var representing the buffer. |
| """ |
| buffer_var = _api.var(name, dtype="handle") |
| return BufferVar(self, buffer_var, content_type) |
| |
| def buffer_ptr(self, buf): |
| """Create pointer variable corresponds to buffer ptr. |
| |
| Parameters |
| ---------- |
| buf : Buffer |
| The buffer to be extracted. |
| |
| Returns |
| ------- |
| ptr : BufferVar |
| The buffer var representing the buffer. |
| """ |
| return BufferVar(self, buf.data, buf.dtype) |
| |
| def likely(self, expr): |
| """Add likely tag for expression. |
| Parameters |
| ---------- |
| expr : Expr |
| The expression. Usually a condition expression. |
| Returns |
| ------- |
| expr : Expr |
| The expression will likely tag. |
| """ |
| return _make.Call(expr.dtype, "likely", [expr], _Call.PureIntrinsic, None, 0) |
| |
| def get(self): |
| """Return the builded IR. |
| |
| Returns |
| ------- |
| stmt : Stmt |
| The result statement. |
| """ |
| seq = self._pop_seq() |
| if self._seq_stack: |
| raise RuntimeError("cannot call get inside construction scope") |
| return seq |
| |
| |
| def create(): |
| """Create a new IRBuilder |
| |
| Returns |
| ------- |
| builder : IRBuilder |
| The created IRBuilder |
| """ |
| return IRBuilder() |
