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Change foreigncall argument order
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Explicitly specify the number of ccall arguments and put the gc root arguments at the end.
This way we can specify variable number of roots, making it easier for typeinf to split the root.
into smaller allocations.
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@yuyichao
yuyichao committed Jul 10, 2017
1 parent 3334724 commit eca9fe5
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Showing 6 changed files with 99 additions and 72 deletions.
27 changes: 21 additions & 6 deletions base/inference.jl
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Original file line number Diff line number Diff line change
Expand Up @@ -3678,6 +3678,10 @@ function substitute!(e::ANY, na::Int, argexprs::Vector{Any}, spsig::ANY, spvals:
for argt
in e.args[3] ]
e.args[3] = svec(argtuple...)
elseif i == 4
@assert isa((e.args[4]::QuoteNode).value, Symbol)
elseif i == 5
@assert isa(e.args[5], Int)
else
e.args[i] = substitute!(e.args[i], na, argexprs, spsig, spvals, offset)
end
Expand Down Expand Up @@ -4752,16 +4756,16 @@ function inlining_pass(e::Expr, sv::InferenceState, stmts, ins)
# by the interpreter and inlining might put in something it can't handle,
# like another ccall (or try to move the variables out into the function)
if e.head === :foreigncall
# 3 is rewritten to 1 below to handle the callee.
i0 = 3
# 5 is rewritten to 1 below to handle the callee.
i0 = 5
isccall = true
elseif is_known_call(e, Core.Intrinsics.llvmcall, sv.src, sv.mod)
i0 = 5
end
has_stmts = false # needed to preserve order-of-execution
prev_stmts_length = length(stmts)
for _i = length(eargs):-1:i0
if isccall && _i == 3
if isccall && _i == 5
i = 1
isccallee = true
else
Expand Down Expand Up @@ -4816,10 +4820,21 @@ function inlining_pass(e::Expr, sv::InferenceState, stmts, ins)
end
if isccall
le = length(eargs)
for i = 4:2:(le - 1)
if eargs[i] === eargs[i + 1]
eargs[i + 1] = 0
nccallargs = eargs[5]::Int
ccallargs = ObjectIdDict()
for i in 6:(5 + nccallargs)
ccallargs[eargs[i]] = nothing
end
i = 6 + nccallargs
while i <= le
rootarg = eargs[i]
if haskey(ccallargs, rootarg)
deleteat!(eargs, i)
le -= 1
elseif i < le
ccallargs[rootarg] = nothing
end
i += 1
end
end
if e.head !== :call
Expand Down
2 changes: 1 addition & 1 deletion doc/src/devdocs/llvm.md
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Original file line number Diff line number Diff line change
Expand Up @@ -260,7 +260,7 @@ pointer which drops the reference to the array value. However, we of course
need to make sure that the array does stay alive while we're doing the `ccall`.
To understand how this is done, first recall the lowering of the above code:
```julia
return $(Expr(:foreigncall, :(:foo), Void, svec(Ptr{Float64}), :($(Expr(:foreigncall, :(:jl_array_ptr), Ptr{Float64}, svec(Any), :(A), 0))), :(A)))
return $(Expr(:foreigncall, :(:foo), Void, svec(Ptr{Float64}), :(:ccall), 1, :($(Expr(:foreigncall, :(:jl_array_ptr), Ptr{Float64}, svec(Any), :(:ccall), 1, :(A)))), :(A)))
```
The last `:(A)`, is an extra argument list inserted during lowering that informs
the code generator which Julia level values need to be kept alive for the
Expand Down
83 changes: 43 additions & 40 deletions src/ccall.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -1380,7 +1380,7 @@ static std::pair<CallingConv::ID, bool> convert_cconv(jl_sym_t *lhd)
if (lhd == jl_symbol("stdcall")) {
return std::make_pair(CallingConv::X86_StdCall, false);
}
else if (lhd == jl_symbol("cdecl")) {
else if (lhd == jl_symbol("cdecl") || lhd == jl_symbol("ccall")) {
return std::make_pair(CallingConv::C, false);
}
else if (lhd == jl_symbol("fastcall")) {
Expand All @@ -1395,7 +1395,7 @@ static std::pair<CallingConv::ID, bool> convert_cconv(jl_sym_t *lhd)
jl_errorf("ccall: invalid calling convention %s", jl_symbol_name(lhd));
}

static const std::string verify_ccall_sig(size_t nargs, jl_value_t *&rt, jl_value_t *at,
static const std::string verify_ccall_sig(size_t nccallargs, jl_value_t *&rt, jl_value_t *at,
jl_unionall_t *unionall_env, jl_svec_t *sparam_vals, const char *funcName,
size_t &nargt, bool &isVa, Type *&lrt, bool &retboxed, bool &static_rt)
{
Expand Down Expand Up @@ -1438,8 +1438,8 @@ static const std::string verify_ccall_sig(size_t nargs, jl_value_t *&rt, jl_valu

nargt = jl_svec_len(at);
isVa = (nargt > 0 && jl_is_vararg_type(jl_svecref(at, nargt - 1)));
if ((!isVa && nargt != (nargs - 2) / 2) ||
( isVa && nargt - 1 > (nargs - 2) / 2))
if ((!isVa && nargt != nccallargs) ||
( isVa && nargt - 1 > nccallargs))
return "ccall: wrong number of arguments to C function";

return "";
Expand All @@ -1448,21 +1448,20 @@ static const std::string verify_ccall_sig(size_t nargs, jl_value_t *&rt, jl_valu
// Expr(:foreigncall, pointer, rettype, (argtypes...), args...)
static jl_cgval_t emit_ccall(jl_codectx_t &ctx, jl_value_t **args, size_t nargs)
{
JL_NARGSV(ccall, 3);
JL_NARGSV(ccall, 5);
args -= 1;
jl_value_t *rt = args[2];
jl_value_t *at = args[3];
assert(jl_is_quotenode(args[4]));
jl_sym_t *cc_sym = *(jl_sym_t**)args[4];
size_t nccallargs = jl_unbox_long(args[5]);
assert(jl_is_symbol(cc_sym));
native_sym_arg_t symarg = {};
JL_GC_PUSH3(&rt, &at, &symarg.gcroot);

CallingConv::ID cc = CallingConv::C;
bool llvmcall = false;
if (nargs % 2 == 0) {
jl_value_t *last = args[nargs];
JL_TYPECHK(ccall, expr, last);
std::tie(cc, llvmcall) = convert_cconv(((jl_expr_t*)last)->head);
nargs -= 1;
}
std::tie(cc, llvmcall) = convert_cconv(cc_sym);

interpret_symbol_arg(ctx, symarg, args[1], "ccall", llvmcall);
Value *&jl_ptr = symarg.jl_ptr;
Expand All @@ -1476,6 +1475,11 @@ static jl_cgval_t emit_ccall(jl_codectx_t &ctx, jl_value_t **args, size_t nargs)
return jl_cgval_t();
}

auto ccallarg = [=] (size_t i) {
assert(i < nccallargs);
return args[6 + i];
};

jl_unionall_t *unionall = (jl_is_method(ctx.linfo->def.method) && jl_is_unionall(ctx.linfo->def.method->sig))
? (jl_unionall_t*)ctx.linfo->def.method->sig
: NULL;
Expand Down Expand Up @@ -1533,7 +1537,7 @@ static jl_cgval_t emit_ccall(jl_codectx_t &ctx, jl_value_t **args, size_t nargs)
bool static_rt;
std::string err = verify_ccall_sig(
/* inputs: */
nargs, rt, at, unionall,
nccallargs, rt, at, unionall,
ctx.spvals_ptr == NULL ? ctx.linfo->sparam_vals : NULL,
ctx.funcName.c_str(),
/* outputs: */
Expand Down Expand Up @@ -1566,8 +1570,8 @@ static jl_cgval_t emit_ccall(jl_codectx_t &ctx, jl_value_t **args, size_t nargs)
if (is_libjulia_func(jl_array_ptr)) {
assert(lrt->isPointerTy());
assert(!isVa && !llvmcall);
assert(nargt==1);
jl_value_t *argi = args[4];
assert(nargt == 1);
jl_value_t *argi = ccallarg(0);
assert(!(jl_is_expr(argi) && ((jl_expr_t*)argi)->head == amp_sym));
jl_cgval_t ary = emit_expr(ctx, argi);
JL_GC_POP();
Expand All @@ -1578,7 +1582,7 @@ static jl_cgval_t emit_ccall(jl_codectx_t &ctx, jl_value_t **args, size_t nargs)
assert(lrt->isPointerTy());
assert(!isVa && !llvmcall);
assert(nargt==1);
jl_value_t *argi = args[4];
jl_value_t *argi = ccallarg(0);
bool addressOf = false;
jl_value_t *tti = jl_svecref(at, 0);
if (jl_is_expr(argi) && ((jl_expr_t*)argi)->head == amp_sym) {
Expand Down Expand Up @@ -1739,7 +1743,7 @@ static jl_cgval_t emit_ccall(jl_codectx_t &ctx, jl_value_t **args, size_t nargs)
else if (is_libjulia_func(jl_is_leaf_type)) {
assert(nargt == 1);
assert(!isVa && !llvmcall);
jl_value_t *arg = args[4];
jl_value_t *arg = ccallarg(0);
jl_value_t *ty = expr_type(ctx, arg);
if (jl_is_type_type(ty) && !jl_is_typevar(jl_tparam0(ty))) {
int isleaf = jl_is_leaf_type(jl_tparam0(ty));
Expand All @@ -1752,14 +1756,14 @@ static jl_cgval_t emit_ccall(jl_codectx_t &ctx, jl_value_t **args, size_t nargs)
else if (is_libjulia_func(jl_function_ptr)) {
assert(nargt == 3);
assert(!isVa && !llvmcall);
jl_value_t *f = static_eval(ctx, args[4], false, false);
jl_value_t *f = static_eval(ctx, ccallarg(0), false, false);
jl_value_t *fargt = nullptr;
JL_GC_PUSH2(&f, &fargt);
jl_value_t *frt = expr_type(ctx, args[6]);
jl_value_t *frt = expr_type(ctx, ccallarg(1));
if (f && (jl_is_type_type((jl_value_t*)frt) && !jl_has_free_typevars(jl_tparam0(frt)))) {
fargt = static_eval(ctx, args[8], true, true);
fargt = static_eval(ctx, ccallarg(2), true, true);
if (!fargt) {
fargt = expr_type(ctx, args[8]);
fargt = expr_type(ctx, ccallarg(2));
if (jl_is_type_type((jl_value_t*)fargt)) {
fargt = jl_tparam0(fargt);
if (jl_has_free_typevars(fargt) || !jl_is_tuple_type(fargt)) {
Expand Down Expand Up @@ -1789,9 +1793,9 @@ static jl_cgval_t emit_ccall(jl_codectx_t &ctx, jl_value_t **args, size_t nargs)
if (llvmf) {
llvmf = prepare_call(llvmf);
// make sure to emit any side-effects that may have been part of the original expression
emit_expr(ctx, args[4]);
emit_expr(ctx, args[6]);
emit_expr(ctx, args[8]);
emit_expr(ctx, ccallarg(0));
emit_expr(ctx, ccallarg(1));
emit_expr(ctx, ccallarg(2));
JL_GC_POP();
JL_GC_POP();
return mark_or_box_ccall_result(ctx, emit_bitcast(ctx, llvmf, lrt),
Expand All @@ -1802,10 +1806,10 @@ static jl_cgval_t emit_ccall(jl_codectx_t &ctx, jl_value_t **args, size_t nargs)
JL_GC_POP();
}
else if (is_libjulia_func(jl_array_isassigned) &&
expr_type(ctx, args[6]) == (jl_value_t*)jl_ulong_type) {
expr_type(ctx, ccallarg(1)) == (jl_value_t*)jl_ulong_type) {
assert(nargt == 2);
jl_value_t *aryex = args[4];
jl_value_t *idxex = args[6];
jl_value_t *aryex = ccallarg(0);
jl_value_t *idxex = ccallarg(1);
jl_value_t *aryty = expr_type(ctx, aryex);
if (jl_is_array_type(aryty)) {
jl_value_t *ety = jl_tparam0(aryty);
Expand All @@ -1832,24 +1836,19 @@ static jl_cgval_t emit_ccall(jl_codectx_t &ctx, jl_value_t **args, size_t nargs)
assert(lrt == T_pint8);
assert(!isVa && !llvmcall);
assert(nargt == 1);
auto obj = emit_pointer_from_objref(ctx, boxed(ctx, emit_expr(ctx, args[4])));
auto obj = emit_pointer_from_objref(ctx, boxed(ctx, emit_expr(ctx, ccallarg(0))));
auto strp = ctx.builder.CreateConstGEP1_32(emit_bitcast(ctx, obj, T_pint8), sizeof(void*));
JL_GC_POP();
return mark_or_box_ccall_result(ctx, strp, retboxed, rt, unionall, static_rt);
}

// emit arguments
jl_cgval_t *argv = (jl_cgval_t*)alloca(sizeof(jl_cgval_t) * (nargs - 3) / 2);
SmallVector<Value*, 16> gc_uses;
jl_cgval_t *argv = (jl_cgval_t*)alloca(sizeof(jl_cgval_t) * nccallargs);
std::vector<bool> addressOf(0);

size_t i;
for (i = 4; i < nargs + 1; i += 2) {
// Current C function parameter
size_t ai = (i - 4) / 2;

for (size_t i = 0; i < nccallargs; i++) {
// Julia (expression) value of current parameter
jl_value_t *argi = args[i];
jl_value_t *argi = ccallarg(i);

// pass the address of the argument rather than the argument itself
if (jl_is_expr(argi) && ((jl_expr_t*)argi)->head == amp_sym) {
Expand All @@ -1860,20 +1859,24 @@ static jl_cgval_t emit_ccall(jl_codectx_t &ctx, jl_value_t **args, size_t nargs)
addressOf.push_back(false);
}

jl_cgval_t &arg = argv[ai];
jl_cgval_t &arg = argv[i];
arg = emit_expr(ctx, (jl_value_t*)argi);

}
SmallVector<Value*, 16> gc_uses;
for (size_t i = nccallargs + 6; i <= nargs; i++) {
// Julia (expression) value of current parameter gcroot
jl_value_t *argi_root = args[i + 1];
jl_value_t *argi_root = args[i];
if (jl_is_long(argi_root))
continue;
jl_cgval_t arg_root = emit_expr(ctx, argi_root);
Value *gcuse = arg_root.gcroot ? ctx.builder.CreateLoad(arg_root.gcroot) : arg_root.V;
if (gcuse)
if (gcuse) {
gc_uses.push_back(gcuse);
}
}

function_sig_t sig(lrt, rt, retboxed, (jl_svec_t*)at, unionall, (nargs - 3) / 2, isVa, cc, llvmcall);
function_sig_t sig(lrt, rt, retboxed, (jl_svec_t*)at, unionall, nccallargs,
isVa, cc, llvmcall);
jl_cgval_t retval = sig.emit_a_ccall(
ctx,
symarg,
Expand Down
8 changes: 4 additions & 4 deletions src/codegen.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -2116,10 +2116,10 @@ static void simple_escape_analysis(jl_codectx_t &ctx, jl_value_t *expr, bool esc
}
else if (e->head == foreigncall_sym) {
simple_escape_analysis(ctx, jl_exprarg(e, 0), esc);
// 2nd and 3d arguments are static
size_t alen = jl_array_dim0(e->args);
for (i = 3; i < alen; i += 2) {
simple_escape_analysis(ctx, jl_exprarg(e, i), esc);
// 2nd to 5th arguments are static
size_t nccallargs = jl_unbox_long(jl_exprarg(e, 4));
for (i = 0; i < nccallargs; i++) {
simple_escape_analysis(ctx, jl_exprarg(e, i + 5), esc);
}
}
else if (e->head == method_sym) {
Expand Down
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