https://github.com/JuliaLang/julia
Tip revision: 0c4fe78de438b1763d2779774bd5ad4ceb0afe8e authored by Valentin Churavy on 01 October 2023, 20:02:48 UTC
add attr to jlpgcstack_func
add attr to jlpgcstack_func
Tip revision: 0c4fe78
optimize.jl
# This file is a part of Julia. License is MIT: https://julialang.org/license
#############
# constants #
#############
# The slot has uses that are not statically dominated by any assignment
# This is implied by `SLOT_USEDUNDEF`.
# If this is not set, all the uses are (statically) dominated by the defs.
# In particular, if a slot has `AssignedOnce && !StaticUndef`, it is an SSA.
const SLOT_STATICUNDEF = 1 # slot might be used before it is defined (structurally)
const SLOT_ASSIGNEDONCE = 16 # slot is assigned to only once
const SLOT_USEDUNDEF = 32 # slot has uses that might raise UndefVarError
# const SLOT_CALLED = 64
# NOTE make sure to sync the flag definitions below with julia.h and `jl_code_info_set_ir` in method.c
const IR_FLAG_NULL = UInt32(0)
# This statement is marked as @inbounds by user.
# Ff replaced by inlining, any contained boundschecks may be removed.
const IR_FLAG_INBOUNDS = UInt32(1) << 0
# This statement is marked as @inline by user
const IR_FLAG_INLINE = UInt32(1) << 1
# This statement is marked as @noinline by user
const IR_FLAG_NOINLINE = UInt32(1) << 2
const IR_FLAG_THROW_BLOCK = UInt32(1) << 3
# This statement may be removed if its result is unused. In particular,
# it must be both :effect_free and :nothrow.
# TODO: Separate these out.
const IR_FLAG_EFFECT_FREE = UInt32(1) << 4
# This statement was proven not to throw
const IR_FLAG_NOTHROW = UInt32(1) << 5
# This is :consistent
const IR_FLAG_CONSISTENT = UInt32(1) << 6
# An optimization pass has updated this statement in a way that may
# have exposed information that inference did not see. Re-running
# inference on this statement may be profitable.
const IR_FLAG_REFINED = UInt32(1) << 7
# This is :noub == ALWAYS_TRUE
const IR_FLAG_NOUB = UInt32(1) << 8
const IR_FLAGS_EFFECTS = IR_FLAG_EFFECT_FREE | IR_FLAG_NOTHROW | IR_FLAG_CONSISTENT | IR_FLAG_NOUB
const TOP_TUPLE = GlobalRef(Core, :tuple)
# This corresponds to the type of `CodeInfo`'s `inlining_cost` field
const InlineCostType = UInt16
const MAX_INLINE_COST = typemax(InlineCostType)
const MIN_INLINE_COST = InlineCostType(10)
const MaybeCompressed = Union{CodeInfo, String}
is_inlineable(@nospecialize src::MaybeCompressed) =
ccall(:jl_ir_inlining_cost, InlineCostType, (Any,), src) != MAX_INLINE_COST
set_inlineable!(src::CodeInfo, val::Bool) =
src.inlining_cost = (val ? MIN_INLINE_COST : MAX_INLINE_COST)
function inline_cost_clamp(x::Int)::InlineCostType
x > MAX_INLINE_COST && return MAX_INLINE_COST
x < MIN_INLINE_COST && return MIN_INLINE_COST
return convert(InlineCostType, x)
end
is_declared_inline(@nospecialize src::MaybeCompressed) =
ccall(:jl_ir_flag_inlining, UInt8, (Any,), src) == 1
is_declared_noinline(@nospecialize src::MaybeCompressed) =
ccall(:jl_ir_flag_inlining, UInt8, (Any,), src) == 2
#####################
# OptimizationState #
#####################
is_source_inferred(@nospecialize src::MaybeCompressed) =
ccall(:jl_ir_flag_inferred, Bool, (Any,), src)
function inlining_policy(interp::AbstractInterpreter,
@nospecialize(src), @nospecialize(info::CallInfo), stmt_flag::UInt32, mi::MethodInstance,
argtypes::Vector{Any})
if isa(src, MaybeCompressed)
is_source_inferred(src) || return nothing
src_inlineable = is_stmt_inline(stmt_flag) || is_inlineable(src)
return src_inlineable ? src : nothing
elseif src === nothing && is_stmt_inline(stmt_flag)
# if this statement is forced to be inlined, make an additional effort to find the
# inferred source in the local cache
# we still won't find a source for recursive call because the "single-level" inlining
# seems to be more trouble and complex than it's worth
inf_result = cache_lookup(optimizer_lattice(interp), mi, argtypes, get_inference_cache(interp))
inf_result === nothing && return nothing
src = inf_result.src
if isa(src, CodeInfo)
src_inferred = is_source_inferred(src)
return src_inferred ? src : nothing
else
return nothing
end
elseif isa(src, IRCode)
return src
elseif isa(src, SemiConcreteResult)
if is_declared_noinline(mi.def::Method)
# For `NativeInterpreter`, `SemiConcreteResult` may be produced for
# a `@noinline`-declared method when it's marked as `@constprop :aggressive`.
# Suppress the inlining here.
return nothing
end
return src
end
return nothing
end
struct InliningState{Interp<:AbstractInterpreter}
edges::Vector{Any}
world::UInt
interp::Interp
end
function InliningState(sv::InferenceState, interp::AbstractInterpreter)
edges = sv.stmt_edges[1]::Vector{Any}
return InliningState(edges, sv.world, interp)
end
function InliningState(interp::AbstractInterpreter)
return InliningState(Any[], get_world_counter(interp), interp)
end
# get `code_cache(::AbstractInterpreter)` from `state::InliningState`
code_cache(state::InliningState) = WorldView(code_cache(state.interp), state.world)
mutable struct OptimizationState{Interp<:AbstractInterpreter}
linfo::MethodInstance
src::CodeInfo
ir::Union{Nothing, IRCode}
stmt_info::Vector{CallInfo}
mod::Module
sptypes::Vector{VarState}
slottypes::Vector{Any}
inlining::InliningState{Interp}
cfg::CFG
unreachable::BitSet
bb_vartables::Vector{Union{Nothing,VarTable}}
insert_coverage::Bool
end
function OptimizationState(sv::InferenceState, interp::AbstractInterpreter)
inlining = InliningState(sv, interp)
return OptimizationState(sv.linfo, sv.src, nothing, sv.stmt_info, sv.mod,
sv.sptypes, sv.slottypes, inlining, sv.cfg,
sv.unreachable, sv.bb_vartables, sv.insert_coverage)
end
function OptimizationState(linfo::MethodInstance, src::CodeInfo, interp::AbstractInterpreter)
# prepare src for running optimization passes if it isn't already
nssavalues = src.ssavaluetypes
if nssavalues isa Int
src.ssavaluetypes = Any[ Any for i = 1:nssavalues ]
else
nssavalues = length(src.ssavaluetypes::Vector{Any})
end
sptypes = sptypes_from_meth_instance(linfo)
nslots = length(src.slotflags)
slottypes = src.slottypes
if slottypes === nothing
slottypes = Any[ Any for i = 1:nslots ]
end
stmt_info = CallInfo[ NoCallInfo() for i = 1:nssavalues ]
# cache some useful state computations
def = linfo.def
mod = isa(def, Method) ? def.module : def
# Allow using the global MI cache, but don't track edges.
# This method is mostly used for unit testing the optimizer
inlining = InliningState(interp)
cfg = compute_basic_blocks(src.code)
unreachable = BitSet()
bb_vartables = Union{VarTable,Nothing}[]
for block = 1:length(cfg.blocks)
push!(bb_vartables, VarState[
VarState(slottypes[slot], src.slotflags[slot] & SLOT_USEDUNDEF != 0)
for slot = 1:nslots
])
end
return OptimizationState(linfo, src, nothing, stmt_info, mod, sptypes, slottypes, inlining, cfg, unreachable, bb_vartables, false)
end
function OptimizationState(linfo::MethodInstance, interp::AbstractInterpreter)
world = get_world_counter(interp)
src = retrieve_code_info(linfo, world)
src === nothing && return nothing
return OptimizationState(linfo, src, interp)
end
function argextype end # imported by EscapeAnalysis
function try_compute_field end # imported by EscapeAnalysis
include("compiler/ssair/heap.jl")
include("compiler/ssair/slot2ssa.jl")
include("compiler/ssair/inlining.jl")
include("compiler/ssair/verify.jl")
include("compiler/ssair/legacy.jl")
include("compiler/ssair/EscapeAnalysis/EscapeAnalysis.jl")
include("compiler/ssair/passes.jl")
include("compiler/ssair/irinterp.jl")
function ir_to_codeinf!(opt::OptimizationState)
(; linfo, src) = opt
src = ir_to_codeinf!(src, opt.ir::IRCode)
opt.ir = nothing
validate_code_in_debug_mode(linfo, src, "optimized")
return src
end
function ir_to_codeinf!(src::CodeInfo, ir::IRCode)
replace_code_newstyle!(src, ir)
widen_all_consts!(src)
src.inferred = true
return src
end
# widen all Const elements in type annotations
function widen_all_consts!(src::CodeInfo)
ssavaluetypes = src.ssavaluetypes::Vector{Any}
for i = 1:length(ssavaluetypes)
ssavaluetypes[i] = widenconst(ssavaluetypes[i])
end
for i = 1:length(src.code)
x = src.code[i]
if isa(x, PiNode)
src.code[i] = PiNode(x.val, widenconst(x.typ))
end
end
src.rettype = widenconst(src.rettype)
return src
end
#########
# logic #
#########
_topmod(sv::OptimizationState) = _topmod(sv.mod)
is_stmt_inline(stmt_flag::UInt32) = stmt_flag & IR_FLAG_INLINE ≠ 0
is_stmt_noinline(stmt_flag::UInt32) = stmt_flag & IR_FLAG_NOINLINE ≠ 0
is_stmt_throw_block(stmt_flag::UInt32) = stmt_flag & IR_FLAG_THROW_BLOCK ≠ 0
function new_expr_effect_flags(𝕃ₒ::AbstractLattice, args::Vector{Any}, src::Union{IRCode,IncrementalCompact}, pattern_match=nothing)
Targ = args[1]
atyp = argextype(Targ, src)
# `Expr(:new)` of unknown type could raise arbitrary TypeError.
typ, isexact = instanceof_tfunc(atyp, true)
if !isexact
atyp = unwrap_unionall(widenconst(atyp))
if isType(atyp) && isTypeDataType(atyp.parameters[1])
typ = atyp.parameters[1]
else
return (false, false, false)
end
isabstracttype(typ) && return (false, false, false)
else
isconcretedispatch(typ) || return (false, false, false)
end
typ = typ::DataType
fcount = datatype_fieldcount(typ)
fcount === nothing && return (false, false, false)
fcount >= length(args) - 1 || return (false, false, false)
for fidx in 1:(length(args) - 1)
farg = args[fidx + 1]
eT = argextype(farg, src)
fT = fieldtype(typ, fidx)
if !isexact && has_free_typevars(fT)
if pattern_match !== nothing && pattern_match(src, typ, fidx, Targ, farg)
continue
end
return (false, false, false)
end
⊑(𝕃ₒ, eT, fT) || return (false, false, false)
end
return (false, true, true)
end
"""
stmt_effect_flags(stmt, rt, src::Union{IRCode,IncrementalCompact}) ->
(consistent::Bool, effect_free_and_nothrow::Bool, nothrow::Bool)
Returns a tuple of `(:consistent, :effect_free_and_nothrow, :nothrow)` flags for a given statement.
"""
function stmt_effect_flags(𝕃ₒ::AbstractLattice, @nospecialize(stmt), @nospecialize(rt), src::Union{IRCode,IncrementalCompact})
# TODO: We're duplicating analysis from inference here.
isa(stmt, PiNode) && return (true, true, true)
isa(stmt, PhiNode) && return (true, true, true)
isa(stmt, ReturnNode) && return (true, false, true)
isa(stmt, GotoNode) && return (true, false, true)
isa(stmt, GotoIfNot) && return (true, false, ⊑(𝕃ₒ, argextype(stmt.cond, src), Bool))
if isa(stmt, GlobalRef)
nothrow = isdefined(stmt.mod, stmt.name)
consistent = nothrow && isconst(stmt.mod, stmt.name)
return (consistent, nothrow, nothrow)
elseif isa(stmt, Expr)
(; head, args) = stmt
if head === :static_parameter
# if we aren't certain enough about the type, it might be an UndefVarError at runtime
sptypes = isa(src, IRCode) ? src.sptypes : src.ir.sptypes
nothrow = !sptypes[args[1]::Int].undef
return (true, nothrow, nothrow)
end
if head === :call
f = argextype(args[1], src)
f = singleton_type(f)
f === nothing && return (false, false, false)
if f === UnionAll
# TODO: This is a weird special case - should be determined in inference
argtypes = Any[argextype(args[arg], src) for arg in 2:length(args)]
nothrow = _builtin_nothrow(𝕃ₒ, f, argtypes, rt)
return (true, nothrow, nothrow)
end
if f === Intrinsics.cglobal
# TODO: these are not yet linearized
return (false, false, false)
end
isa(f, Builtin) || return (false, false, false)
# Needs to be handled in inlining to look at the callee effects
f === Core._apply_iterate && return (false, false, false)
argtypes = Any[argextype(args[arg], src) for arg in 1:length(args)]
effects = builtin_effects(𝕃ₒ, f, ArgInfo(args, argtypes), rt)
consistent = is_consistent(effects)
effect_free = is_effect_free(effects)
nothrow = is_nothrow(effects)
return (consistent, effect_free & nothrow, nothrow)
elseif head === :new
return new_expr_effect_flags(𝕃ₒ, args, src)
elseif head === :foreigncall
effects = foreigncall_effects(stmt) do @nospecialize x
argextype(x, src)
end
consistent = is_consistent(effects)
effect_free = is_effect_free(effects)
nothrow = is_nothrow(effects)
return (consistent, effect_free & nothrow, nothrow)
elseif head === :new_opaque_closure
length(args) < 4 && return (false, false, false)
typ = argextype(args[1], src)
typ, isexact = instanceof_tfunc(typ, true)
isexact || return (false, false, false)
⊑(𝕃ₒ, typ, Tuple) || return (false, false, false)
rt_lb = argextype(args[2], src)
rt_ub = argextype(args[3], src)
source = argextype(args[4], src)
if !(⊑(𝕃ₒ, rt_lb, Type) && ⊑(𝕃ₒ, rt_ub, Type) && ⊑(𝕃ₒ, source, Method))
return (false, false, false)
end
return (false, true, true)
elseif head === :inbounds
return (true, true, true)
elseif head === :boundscheck || head === :isdefined || head === :the_exception || head === :copyast
return (false, true, true)
else
# e.g. :loopinfo
return (false, false, false)
end
end
isa(stmt, SlotNumber) && error("unexpected IR elements")
return (true, true, true)
end
"""
argextype(x, src::Union{IRCode,IncrementalCompact}) -> t
argextype(x, src::CodeInfo, sptypes::Vector{VarState}) -> t
Return the type of value `x` in the context of inferred source `src`.
Note that `t` might be an extended lattice element.
Use `widenconst(t)` to get the native Julia type of `x`.
"""
argextype(@nospecialize(x), ir::IRCode, sptypes::Vector{VarState} = ir.sptypes) =
argextype(x, ir, sptypes, ir.argtypes)
function argextype(@nospecialize(x), compact::IncrementalCompact, sptypes::Vector{VarState} = compact.ir.sptypes)
isa(x, AnySSAValue) && return types(compact)[x]
return argextype(x, compact, sptypes, compact.ir.argtypes)
end
argextype(@nospecialize(x), src::CodeInfo, sptypes::Vector{VarState}) = argextype(x, src, sptypes, src.slottypes::Vector{Any})
function argextype(
@nospecialize(x), src::Union{IRCode,IncrementalCompact,CodeInfo},
sptypes::Vector{VarState}, slottypes::Vector{Any})
if isa(x, Expr)
if x.head === :static_parameter
return sptypes[x.args[1]::Int].typ
elseif x.head === :boundscheck
return Bool
elseif x.head === :copyast
return argextype(x.args[1], src, sptypes, slottypes)
end
Core.println("argextype called on Expr with head ", x.head,
" which is not valid for IR in argument-position.")
@assert false
elseif isa(x, SlotNumber)
return slottypes[x.id]
elseif isa(x, SSAValue)
return abstract_eval_ssavalue(x, src)
elseif isa(x, Argument)
return slottypes[x.n]
elseif isa(x, QuoteNode)
return Const(x.value)
elseif isa(x, GlobalRef)
return abstract_eval_globalref(x)
elseif isa(x, PhiNode)
return Any
elseif isa(x, PiNode)
return x.typ
else
return Const(x)
end
end
abstract_eval_ssavalue(s::SSAValue, src::CodeInfo) = abstract_eval_ssavalue(s, src.ssavaluetypes::Vector{Any})
abstract_eval_ssavalue(s::SSAValue, src::Union{IRCode,IncrementalCompact}) = types(src)[s]
"""
finish(interp::AbstractInterpreter, opt::OptimizationState,
ir::IRCode, caller::InferenceResult)
Post-process information derived by Julia-level optimizations for later use.
In particular, this function determines the inlineability of the optimized code.
"""
function finish(interp::AbstractInterpreter, opt::OptimizationState,
ir::IRCode, caller::InferenceResult)
(; src, linfo) = opt
(; def, specTypes) = linfo
force_noinline = is_declared_noinline(src)
# compute inlining and other related optimizations
result = caller.result
@assert !(result isa LimitedAccuracy)
result = widenslotwrapper(result)
opt.ir = ir
# determine and cache inlineability
if !force_noinline
sig = unwrap_unionall(specTypes)
if !(isa(sig, DataType) && sig.name === Tuple.name)
force_noinline = true
end
if !is_declared_inline(src) && result === Bottom
force_noinline = true
end
end
if force_noinline
set_inlineable!(src, false)
elseif isa(def, Method)
if is_declared_inline(src) && isdispatchtuple(specTypes)
# obey @inline declaration if a dispatch barrier would not help
set_inlineable!(src, true)
else
# compute the cost (size) of inlining this code
params = OptimizationParams(interp)
cost_threshold = default = params.inline_cost_threshold
if ⊑(optimizer_lattice(interp), result, Tuple) && !isconcretetype(widenconst(result))
cost_threshold += params.inline_tupleret_bonus
end
# if the method is declared as `@inline`, increase the cost threshold 20x
if is_declared_inline(src)
cost_threshold += 19*default
end
# a few functions get special treatment
if def.module === _topmod(def.module)
name = def.name
if name === :iterate || name === :unsafe_convert || name === :cconvert
cost_threshold += 4*default
end
end
src.inlining_cost = inline_cost(ir, params, cost_threshold)
end
end
return nothing
end
function visit_bb_phis!(callback, ir::IRCode, bb::Int)
stmts = ir.cfg.blocks[bb].stmts
for idx in stmts
stmt = ir[SSAValue(idx)][:stmt]
if !isa(stmt, PhiNode)
if !is_valid_phiblock_stmt(stmt)
return
end
else
callback(idx)
end
end
end
function any_stmt_may_throw(ir::IRCode, bb::Int)
for stmt in ir.cfg.blocks[bb].stmts
if (ir[SSAValue(stmt)][:flag] & IR_FLAG_NOTHROW) != 0
return true
end
end
return false
end
function conditional_successors_may_throw(lazypostdomtree::LazyPostDomtree, ir::IRCode, bb::Int)
visited = BitSet((bb,))
worklist = Int[bb]
while !isempty(worklist)
thisbb = pop!(worklist)
for succ in ir.cfg.blocks[thisbb].succs
succ in visited && continue
push!(visited, succ)
postdominates(get!(lazypostdomtree), succ, thisbb) && continue
any_stmt_may_throw(ir, succ) && return true
push!(worklist, succ)
end
end
return false
end
struct AugmentedDomtree
cfg::CFG
domtree::DomTree
end
mutable struct LazyAugmentedDomtree
const ir::IRCode
agdomtree::AugmentedDomtree
LazyAugmentedDomtree(ir::IRCode) = new(ir)
end
function get!(lazyagdomtree::LazyAugmentedDomtree)
isdefined(lazyagdomtree, :agdomtree) && return lazyagdomtree.agdomtree
ir = lazyagdomtree.ir
cfg = copy(ir.cfg)
# Add a virtual basic block to represent the exit
push!(cfg.blocks, BasicBlock(StmtRange(0:-1)))
for bb = 1:(length(cfg.blocks)-1)
terminator = ir[SSAValue(last(cfg.blocks[bb].stmts))][:stmt]
if isa(terminator, ReturnNode) && isdefined(terminator, :val)
cfg_insert_edge!(cfg, bb, length(cfg.blocks))
end
end
domtree = construct_domtree(cfg.blocks)
return lazyagdomtree.agdomtree = AugmentedDomtree(cfg, domtree)
end
# TODO refine `:effect_free` using EscapeAnalysis
mutable struct PostOptAnalysisState
const result::InferenceResult
const ir::IRCode
const inconsistent::BitSetBoundedMinPrioritySet
const tpdum::TwoPhaseDefUseMap
const lazypostdomtree::LazyPostDomtree
const lazyagdomtree::LazyAugmentedDomtree
all_retpaths_consistent::Bool
all_effect_free::Bool
all_nothrow::Bool
all_noub::Bool
any_conditional_ub::Bool
function PostOptAnalysisState(result::InferenceResult, ir::IRCode)
inconsistent = BitSetBoundedMinPrioritySet(length(ir.stmts))
tpdum = TwoPhaseDefUseMap(length(ir.stmts))
lazypostdomtree = LazyPostDomtree(ir)
lazyagdomtree = LazyAugmentedDomtree(ir)
return new(result, ir, inconsistent, tpdum, lazypostdomtree, lazyagdomtree, true, true, true, true, false)
end
end
give_up_refinements!(sv::PostOptAnalysisState) =
sv.all_retpaths_consistent = sv.all_effect_free = sv.all_nothrow = sv.all_noub = false
function any_refinable(sv::PostOptAnalysisState)
effects = sv.result.ipo_effects
return ((!is_consistent(effects) & sv.all_retpaths_consistent) |
(!is_effect_free(effects) & sv.all_effect_free) |
(!is_nothrow(effects) & sv.all_nothrow) |
(!is_noub(effects) & sv.all_noub))
end
function refine_effects!(sv::PostOptAnalysisState)
any_refinable(sv) || return false
effects = sv.result.ipo_effects
sv.result.ipo_effects = Effects(effects;
consistent = sv.all_retpaths_consistent ? ALWAYS_TRUE : effects.consistent,
effect_free = sv.all_effect_free ? ALWAYS_TRUE : effects.effect_free,
nothrow = sv.all_nothrow ? true : effects.nothrow,
noub = sv.all_noub ? (sv.any_conditional_ub ? NOUB_IF_NOINBOUNDS : ALWAYS_TRUE) : effects.noub)
return true
end
function is_ipo_dataflow_analysis_profitable(effects::Effects)
return !(is_consistent(effects) && is_effect_free(effects) &&
is_nothrow(effects) && is_noub(effects))
end
function is_getfield_with_boundscheck_arg(@nospecialize(stmt), sv::PostOptAnalysisState)
is_known_call(stmt, getfield, sv.ir) || return false
length(stmt.args) < 4 && return false
boundscheck = stmt.args[end]
argextype(boundscheck, sv.ir) === Bool || return false
isa(boundscheck, SSAValue) || return false
return true
end
function is_conditional_noub(inst::Instruction, sv::PostOptAnalysisState)
# Special case: `:boundscheck` into `getfield`
stmt = inst[:stmt]
is_getfield_with_boundscheck_arg(stmt, sv) || return false
barg = stmt.args[end]
bstmt = sv.ir[barg][:stmt]
isexpr(bstmt, :boundscheck) || return false
# If IR_FLAG_INBOUNDS is already set, no more conditional ub
(!isempty(bstmt.args) && bstmt.args[1] === false) && return false
sv.any_conditional_ub = true
return true
end
function scan_non_dataflow_flags!(inst::Instruction, sv::PostOptAnalysisState)
flag = inst[:flag]
stmt = inst[:stmt]
if !isterminator(stmt) && stmt !== nothing
# ignore control flow node – they are not removable on their own and thus not
# have `IR_FLAG_EFFECT_FREE` but still do not taint `:effect_free`-ness of
# the whole method invocation
sv.all_effect_free &= !iszero(flag & IR_FLAG_EFFECT_FREE)
end
sv.all_nothrow &= !iszero(flag & IR_FLAG_NOTHROW)
if iszero(flag & IR_FLAG_NOUB)
if !is_conditional_noub(inst, sv)
sv.all_noub = false
end
end
end
function scan_inconsistency!(inst::Instruction, idx::Int, sv::PostOptAnalysisState)
flag = inst[:flag]
stmt_inconsistent = iszero(flag & IR_FLAG_CONSISTENT)
stmt = inst[:stmt]
# Special case: For getfield, we allow inconsistency of the :boundscheck argument
(; inconsistent, tpdum) = sv
if is_getfield_with_boundscheck_arg(stmt, sv)
for i = 1:(length(stmt.args)-1)
val = stmt.args[i]
if isa(val, SSAValue)
stmt_inconsistent |= val.id in inconsistent
count!(tpdum, val)
end
end
else
for ur in userefs(stmt)
val = ur[]
if isa(val, SSAValue)
stmt_inconsistent |= val.id in inconsistent
count!(tpdum, val)
end
end
end
stmt_inconsistent && push!(inconsistent, idx)
return stmt_inconsistent
end
struct ScanStmt
sv::PostOptAnalysisState
end
function ((; sv)::ScanStmt)(inst::Instruction, idx::Int, lstmt::Int, bb::Int)
stmt = inst[:stmt]
flag = inst[:flag]
if isexpr(stmt, :enter)
# try/catch not yet modeled
give_up_refinements!(sv)
return nothing
end
scan_non_dataflow_flags!(inst, sv)
stmt_inconsistent = scan_inconsistency!(inst, idx, sv)
if stmt_inconsistent && idx == lstmt
if isa(stmt, ReturnNode) && isdefined(stmt, :val)
sv.all_retpaths_consistent = false
elseif isa(stmt, GotoIfNot)
# Conditional Branch with inconsistent condition.
# If we do not know this function terminates, taint consistency, now,
# :consistent requires consistent termination. TODO: Just look at the
# inconsistent region.
if !sv.result.ipo_effects.terminates
sv.all_retpaths_consistent = false
elseif conditional_successors_may_throw(sv.lazypostdomtree, sv.ir, bb)
# Check if there are potential throws that require
sv.all_retpaths_consistent = false
else
(; cfg, domtree) = get!(sv.lazyagdomtree)
for succ in iterated_dominance_frontier(cfg, BlockLiveness(sv.ir.cfg.blocks[bb].succs, nothing), domtree)
if succ == length(cfg.blocks)
# Phi node in the virtual exit -> We have a conditional
# return. TODO: Check if all the retvals are egal.
sv.all_retpaths_consistent = false
else
visit_bb_phis!(sv.ir, succ) do phiidx::Int
push!(sv.inconsistent, phiidx)
end
end
end
end
end
end
# bail out early if there are no possibilities to refine the effects
if !any_refinable(sv)
return nothing
end
return true
end
function check_inconsistentcy!(sv::PostOptAnalysisState, scanner::BBScanner)
scan!(ScanStmt(sv), scanner, true)
complete!(sv.tpdum); push!(scanner.bb_ip, 1)
populate_def_use_map!(sv.tpdum, scanner)
(; ir, inconsistent, tpdum) = sv
stmt_ip = BitSetBoundedMinPrioritySet(length(ir.stmts))
for def in sv.inconsistent
for use in tpdum[def]
if !(use in inconsistent)
push!(inconsistent, use)
append!(stmt_ip, tpdum[use])
end
end
end
while !isempty(stmt_ip)
idx = popfirst!(stmt_ip)
inst = ir[SSAValue(idx)]
stmt = inst[:stmt]
if is_getfield_with_boundscheck_arg(stmt, sv)
any_non_boundscheck_inconsistent = false
for i = 1:(length(stmt.args)-1)
val = stmt.args[i]
if isa(val, SSAValue)
any_non_boundscheck_inconsistent |= val.id in inconsistent
any_non_boundscheck_inconsistent && break
end
end
any_non_boundscheck_inconsistent || continue
elseif isa(stmt, ReturnNode)
sv.all_retpaths_consistent = false
else isa(stmt, GotoIfNot)
bb = block_for_inst(ir, idx)
cfg = ir.cfg
blockliveness = BlockLiveness(cfg.blocks[bb].succs, nothing)
domtree = construct_domtree(cfg.blocks)
for succ in iterated_dominance_frontier(cfg, blockliveness, domtree)
visit_bb_phis!(ir, succ) do phiidx::Int
push!(inconsistent, phiidx)
push!(stmt_ip, phiidx)
end
end
end
sv.all_retpaths_consistent || break
append!(inconsistent, tpdum[idx])
append!(stmt_ip, tpdum[idx])
end
end
function ipo_dataflow_analysis!(interp::AbstractInterpreter, ir::IRCode, result::InferenceResult)
is_ipo_dataflow_analysis_profitable(result.ipo_effects) || return false
sv = PostOptAnalysisState(result, ir)
scanner = BBScanner(ir)
completed_scan = scan!(ScanStmt(sv), scanner, true)
if !completed_scan
if sv.all_retpaths_consistent
check_inconsistentcy!(sv, scanner)
else
# No longer any dataflow concerns, just scan the flags
scan!(scanner, false) do inst::Instruction, idx::Int, lstmt::Int, bb::Int
scan_non_dataflow_flags!(inst, sv)
# bail out early if there are no possibilities to refine the effects
if !any_refinable(sv)
return nothing
end
return true
end
end
end
return refine_effects!(sv)
end
# run the optimization work
function optimize(interp::AbstractInterpreter, opt::OptimizationState, caller::InferenceResult)
@timeit "optimizer" ir = run_passes_ipo_safe(opt.src, opt, caller)
ipo_dataflow_analysis!(interp, ir, caller)
return finish(interp, opt, ir, caller)
end
macro pass(name, expr)
optimize_until = esc(:optimize_until)
stage = esc(:__stage__)
macrocall = :(@timeit $(esc(name)) $(esc(expr)))
macrocall.args[2] = __source__ # `@timeit` may want to use it
quote
$macrocall
matchpass($optimize_until, ($stage += 1), $(esc(name))) && $(esc(:(@goto __done__)))
end
end
matchpass(optimize_until::Int, stage, _) = optimize_until == stage
matchpass(optimize_until::String, _, name) = optimize_until == name
matchpass(::Nothing, _, _) = false
function run_passes_ipo_safe(
ci::CodeInfo,
sv::OptimizationState,
caller::InferenceResult,
optimize_until = nothing, # run all passes by default
)
__stage__ = 0 # used by @pass
# NOTE: The pass name MUST be unique for `optimize_until::AbstractString` to work
@pass "convert" ir = convert_to_ircode(ci, sv)
@pass "slot2reg" ir = slot2reg(ir, ci, sv)
# TODO: Domsorting can produce an updated domtree - no need to recompute here
@pass "compact 1" ir = compact!(ir)
@pass "Inlining" ir = ssa_inlining_pass!(ir, sv.inlining, ci.propagate_inbounds)
# @timeit "verify 2" verify_ir(ir)
@pass "compact 2" ir = compact!(ir)
@pass "SROA" ir = sroa_pass!(ir, sv.inlining)
@pass "ADCE" ir = adce_pass!(ir, sv.inlining)
@pass "compact 3" ir = compact!(ir, true)
if JLOptions().debug_level == 2
@timeit "verify 3" (verify_ir(ir, true, false, optimizer_lattice(sv.inlining.interp)); verify_linetable(ir.linetable))
end
@label __done__ # used by @pass
return ir
end
function convert_to_ircode(ci::CodeInfo, sv::OptimizationState)
linetable = ci.linetable
if !isa(linetable, Vector{LineInfoNode})
linetable = collect(LineInfoNode, linetable::Vector{Any})::Vector{LineInfoNode}
end
# Update control-flow to reflect any unreachable branches.
ssavaluetypes = ci.ssavaluetypes::Vector{Any}
code = copy_exprargs(ci.code)
for i = 1:length(code)
expr = code[i]
if !(i in sv.unreachable) && isa(expr, GotoIfNot)
# Replace this live GotoIfNot with:
# - no-op if :nothrow and the branch target is unreachable
# - cond if :nothrow and both targets are unreachable
# - typeassert if must-throw
block = block_for_inst(sv.cfg, i)
if ssavaluetypes[i] === Bottom
destblock = block_for_inst(sv.cfg, expr.dest)
cfg_delete_edge!(sv.cfg, block, block + 1)
((block + 1) != destblock) && cfg_delete_edge!(sv.cfg, block, destblock)
expr = Expr(:call, Core.typeassert, expr.cond, Bool)
elseif i + 1 in sv.unreachable
@assert (ci.ssaflags[i] & IR_FLAG_NOTHROW) != 0
cfg_delete_edge!(sv.cfg, block, block + 1)
expr = GotoNode(expr.dest)
elseif expr.dest in sv.unreachable
@assert (ci.ssaflags[i] & IR_FLAG_NOTHROW) != 0
cfg_delete_edge!(sv.cfg, block, block_for_inst(sv.cfg, expr.dest))
expr = nothing
end
code[i] = expr
end
end
# Go through and add an unreachable node after every
# Union{} call. Then reindex labels.
stmtinfo = sv.stmt_info
codelocs = ci.codelocs
ssaflags = ci.ssaflags
meta = Expr[]
idx = 1
oldidx = 1
nstmts = length(code)
ssachangemap = labelchangemap = blockchangemap = nothing
prevloc = zero(eltype(ci.codelocs))
while idx <= length(code)
codeloc = codelocs[idx]
if sv.insert_coverage && codeloc != prevloc && codeloc != 0
# insert a side-effect instruction before the current instruction in the same basic block
insert!(code, idx, Expr(:code_coverage_effect))
insert!(codelocs, idx, codeloc)
insert!(ssavaluetypes, idx, Nothing)
insert!(stmtinfo, idx, NoCallInfo())
insert!(ssaflags, idx, IR_FLAG_NULL)
if ssachangemap === nothing
ssachangemap = fill(0, nstmts)
end
if labelchangemap === nothing
labelchangemap = fill(0, nstmts)
end
ssachangemap[oldidx] += 1
if oldidx < length(labelchangemap)
labelchangemap[oldidx + 1] += 1
end
if blockchangemap === nothing
blockchangemap = fill(0, length(sv.cfg.blocks))
end
blockchangemap[block_for_inst(sv.cfg, oldidx)] += 1
idx += 1
prevloc = codeloc
end
if ssavaluetypes[idx] === Union{} && !(oldidx in sv.unreachable)
# We should have converted any must-throw terminators to an equivalent w/o control-flow edges
@assert !isterminator(code[idx])
block = block_for_inst(sv.cfg, oldidx)
block_end = last(sv.cfg.blocks[block].stmts) + (idx - oldidx)
# Delete all successors to this basic block
for succ in sv.cfg.blocks[block].succs
preds = sv.cfg.blocks[succ].preds
deleteat!(preds, findfirst(x::Int->x==block, preds)::Int)
end
empty!(sv.cfg.blocks[block].succs)
if !(idx < length(code) && isa(code[idx + 1], ReturnNode) && !isdefined((code[idx + 1]::ReturnNode), :val))
# Any statements from here to the end of the block have been wrapped in Core.Const(...)
# by type inference (effectively deleting them). Only task left is to replace the block
# terminator with an explicit `unreachable` marker.
if block_end > idx
code[block_end] = ReturnNode()
codelocs[block_end] = codelocs[idx]
ssavaluetypes[block_end] = Union{}
stmtinfo[block_end] = NoCallInfo()
ssaflags[block_end] = IR_FLAG_NOTHROW
# Verify that type-inference did its job
if JLOptions().debug_level == 2
for i = (oldidx + 1):last(sv.cfg.blocks[block].stmts)
@assert i in sv.unreachable
end
end
idx += block_end - idx
else
insert!(code, idx + 1, ReturnNode())
insert!(codelocs, idx + 1, codelocs[idx])
insert!(ssavaluetypes, idx + 1, Union{})
insert!(stmtinfo, idx + 1, NoCallInfo())
insert!(ssaflags, idx + 1, IR_FLAG_NOTHROW)
if ssachangemap === nothing
ssachangemap = fill(0, nstmts)
end
if labelchangemap === nothing
labelchangemap = sv.insert_coverage ? fill(0, nstmts) : ssachangemap
end
if oldidx < length(ssachangemap)
ssachangemap[oldidx + 1] += 1
sv.insert_coverage && (labelchangemap[oldidx + 1] += 1)
end
if blockchangemap === nothing
blockchangemap = fill(0, length(sv.cfg.blocks))
end
blockchangemap[block] += 1
idx += 1
end
oldidx = last(sv.cfg.blocks[block].stmts)
end
end
idx += 1
oldidx += 1
end
if ssachangemap !== nothing && labelchangemap !== nothing
renumber_ir_elements!(code, ssachangemap, labelchangemap)
end
if blockchangemap !== nothing
renumber_cfg_stmts!(sv.cfg, blockchangemap)
end
for i = 1:length(code)
code[i] = process_meta!(meta, code[i])
end
strip_trailing_junk!(ci, sv.cfg, code, stmtinfo)
types = Any[]
stmts = InstructionStream(code, types, stmtinfo, codelocs, ssaflags)
# NOTE this `argtypes` contains types of slots yet: it will be modified to contain the
# types of call arguments only once `slot2reg` converts this `IRCode` to the SSA form
# and eliminates slots (see below)
argtypes = sv.slottypes
return IRCode(stmts, sv.cfg, linetable, argtypes, meta, sv.sptypes)
end
function process_meta!(meta::Vector{Expr}, @nospecialize stmt)
if isexpr(stmt, :meta) && length(stmt.args) ≥ 1
push!(meta, stmt)
return nothing
end
return stmt
end
function slot2reg(ir::IRCode, ci::CodeInfo, sv::OptimizationState)
# need `ci` for the slot metadata, IR for the code
svdef = sv.linfo.def
nargs = isa(svdef, Method) ? Int(svdef.nargs) : 0
@timeit "domtree 1" domtree = construct_domtree(ir.cfg.blocks)
defuse_insts = scan_slot_def_use(nargs, ci, ir.stmts.stmt)
𝕃ₒ = optimizer_lattice(sv.inlining.interp)
@timeit "construct_ssa" ir = construct_ssa!(ci, ir, sv, domtree, defuse_insts, 𝕃ₒ) # consumes `ir`
# NOTE now we have converted `ir` to the SSA form and eliminated slots
# let's resize `argtypes` now and remove unnecessary types for the eliminated slots
resize!(ir.argtypes, nargs)
return ir
end
## Computing the cost of a function body
# saturating sum (inputs are non-negative), prevents overflow with typemax(Int) below
plus_saturate(x::Int, y::Int) = max(x, y, x+y)
# known return type
isknowntype(@nospecialize T) = (T === Union{}) || isa(T, Const) || isconcretetype(widenconst(T))
function statement_cost(ex::Expr, line::Int, src::Union{CodeInfo, IRCode}, sptypes::Vector{VarState},
params::OptimizationParams, error_path::Bool = false)
head = ex.head
if is_meta_expr_head(head)
return 0
elseif head === :call
farg = ex.args[1]
ftyp = argextype(farg, src, sptypes)
if ftyp === IntrinsicFunction && farg isa SSAValue
# if this comes from code that was already inlined into another function,
# Consts have been widened. try to recover in simple cases.
farg = isa(src, CodeInfo) ? src.code[farg.id] : src[farg][:stmt]
if isa(farg, GlobalRef) || isa(farg, QuoteNode) || isa(farg, IntrinsicFunction) || isexpr(farg, :static_parameter)
ftyp = argextype(farg, src, sptypes)
end
end
f = singleton_type(ftyp)
if isa(f, IntrinsicFunction)
iidx = Int(reinterpret(Int32, f::IntrinsicFunction)) + 1
if !isassigned(T_IFUNC_COST, iidx)
# unknown/unhandled intrinsic
return params.inline_nonleaf_penalty
end
return T_IFUNC_COST[iidx]
end
if isa(f, Builtin) && f !== invoke
# The efficiency of operations like a[i] and s.b
# depend strongly on whether the result can be
# inferred, so check the type of ex
if f === Core.getfield || f === Core.tuple || f === Core.getglobal
# we might like to penalize non-inferrability, but
# tuple iteration/destructuring makes that impossible
# return plus_saturate(argcost, isknowntype(extyp) ? 1 : params.inline_nonleaf_penalty)
return 0
elseif (f === Core.arrayref || f === Core.const_arrayref || f === Core.arrayset) && length(ex.args) >= 3
atyp = argextype(ex.args[3], src, sptypes)
return isknowntype(atyp) ? 4 : error_path ? params.inline_error_path_cost : params.inline_nonleaf_penalty
elseif f === typeassert && isconstType(widenconst(argextype(ex.args[3], src, sptypes)))
return 1
end
fidx = find_tfunc(f)
if fidx === nothing
# unknown/unhandled builtin
# Use the generic cost of a direct function call
return 20
end
return T_FFUNC_COST[fidx]
end
extyp = line == -1 ? Any : argextype(SSAValue(line), src, sptypes)
if extyp === Union{}
return 0
end
return error_path ? params.inline_error_path_cost : params.inline_nonleaf_penalty
elseif head === :foreigncall || head === :invoke || head === :invoke_modify
# Calls whose "return type" is Union{} do not actually return:
# they are errors. Since these are not part of the typical
# run-time of the function, we omit them from
# consideration. This way, non-inlined error branches do not
# prevent inlining.
extyp = line == -1 ? Any : argextype(SSAValue(line), src, sptypes)
return extyp === Union{} ? 0 : 20
elseif head === :(=)
if ex.args[1] isa GlobalRef
cost = 20
else
cost = 0
end
a = ex.args[2]
if a isa Expr
cost = plus_saturate(cost, statement_cost(a, -1, src, sptypes, params, error_path))
end
return cost
elseif head === :copyast
return 100
elseif head === :enter
# try/catch is a couple function calls,
# but don't inline functions with try/catch
# since these aren't usually performance-sensitive functions,
# and llvm is more likely to miscompile them when these functions get large
return typemax(Int)
end
return 0
end
function statement_or_branch_cost(@nospecialize(stmt), line::Int, src::Union{CodeInfo, IRCode}, sptypes::Vector{VarState},
params::OptimizationParams)
thiscost = 0
dst(tgt) = isa(src, IRCode) ? first(src.cfg.blocks[tgt].stmts) : tgt
if stmt isa Expr
thiscost = statement_cost(stmt, line, src, sptypes, params,
is_stmt_throw_block(isa(src, IRCode) ? src.stmts.flag[line] : src.ssaflags[line]))::Int
elseif stmt isa GotoNode
# loops are generally always expensive
# but assume that forward jumps are already counted for from
# summing the cost of the not-taken branch
thiscost = dst(stmt.label) < line ? 40 : 0
elseif stmt isa GotoIfNot
thiscost = dst(stmt.dest) < line ? 40 : 0
end
return thiscost
end
function inline_cost(ir::IRCode, params::OptimizationParams,
cost_threshold::Integer=params.inline_cost_threshold)::InlineCostType
bodycost::Int = 0
for line = 1:length(ir.stmts)
stmt = ir[SSAValue(line)][:stmt]
thiscost = statement_or_branch_cost(stmt, line, ir, ir.sptypes, params)
bodycost = plus_saturate(bodycost, thiscost)
bodycost > cost_threshold && return MAX_INLINE_COST
end
return inline_cost_clamp(bodycost)
end
function statement_costs!(cost::Vector{Int}, body::Vector{Any}, src::Union{CodeInfo, IRCode}, sptypes::Vector{VarState}, params::OptimizationParams)
maxcost = 0
for line = 1:length(body)
stmt = body[line]
thiscost = statement_or_branch_cost(stmt, line, src, sptypes,
params)
cost[line] = thiscost
if thiscost > maxcost
maxcost = thiscost
end
end
return maxcost
end
function renumber_ir_elements!(body::Vector{Any}, cfg::Union{CFG,Nothing}, ssachangemap::Vector{Int})
return renumber_ir_elements!(body, cfg, ssachangemap, ssachangemap)
end
function cumsum_ssamap!(ssachangemap::Vector{Int})
any_change = false
rel_change = 0
for i = 1:length(ssachangemap)
val = ssachangemap[i]
any_change |= val ≠ 0
rel_change += val
if val == -1
# Keep a marker that this statement was deleted
ssachangemap[i] = typemin(Int)
else
ssachangemap[i] = rel_change
end
end
return any_change
end
function renumber_ir_elements!(body::Vector{Any}, ssachangemap::Vector{Int}, labelchangemap::Vector{Int})
any_change = cumsum_ssamap!(labelchangemap)
if ssachangemap !== labelchangemap
any_change |= cumsum_ssamap!(ssachangemap)
end
any_change || return
for i = 1:length(body)
el = body[i]
if isa(el, GotoNode)
body[i] = GotoNode(el.label + labelchangemap[el.label])
elseif isa(el, GotoIfNot)
cond = el.cond
if isa(cond, SSAValue)
cond = SSAValue(cond.id + ssachangemap[cond.id])
end
was_deleted = labelchangemap[el.dest] == typemin(Int)
body[i] = was_deleted ? cond : GotoIfNot(cond, el.dest + labelchangemap[el.dest])
elseif isa(el, ReturnNode)
if isdefined(el, :val)
val = el.val
if isa(val, SSAValue)
body[i] = ReturnNode(SSAValue(val.id + ssachangemap[val.id]))
end
end
elseif isa(el, SSAValue)
body[i] = SSAValue(el.id + ssachangemap[el.id])
elseif isa(el, PhiNode)
i = 1
edges = el.edges
values = el.values
while i <= length(edges)
was_deleted = ssachangemap[edges[i]] == typemin(Int)
if was_deleted
deleteat!(edges, i)
deleteat!(values, i)
else
edges[i] += ssachangemap[edges[i]]
val = values[i]
if isa(val, SSAValue)
values[i] = SSAValue(val.id + ssachangemap[val.id])
end
i += 1
end
end
elseif isa(el, Expr)
if el.head === :(=) && el.args[2] isa Expr
el = el.args[2]::Expr
end
if el.head === :enter
tgt = el.args[1]::Int
el.args[1] = tgt + labelchangemap[tgt]
elseif !is_meta_expr_head(el.head)
args = el.args
for i = 1:length(args)
el = args[i]
if isa(el, SSAValue)
args[i] = SSAValue(el.id + ssachangemap[el.id])
end
end
end
end
end
end
function renumber_cfg_stmts!(cfg::CFG, blockchangemap::Vector{Int})
cumsum_ssamap!(blockchangemap) || return
for i = 1:length(cfg.blocks)
old_range = cfg.blocks[i].stmts
new_range = StmtRange(first(old_range) + ((i > 1) ? blockchangemap[i - 1] : 0),
last(old_range) + blockchangemap[i])
cfg.blocks[i] = BasicBlock(cfg.blocks[i], new_range)
if i <= length(cfg.index)
cfg.index[i] = cfg.index[i] + blockchangemap[i]
end
end
end
