1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
|
#pragma once
#include "eval.hh"
#define LocalNoInline(f) static f __attribute__((noinline)); f
#define LocalNoInlineNoReturn(f) static f __attribute__((noinline, noreturn)); f
namespace nix {
LocalNoInlineNoReturn(void throwEvalError(const Pos & pos, const char * s))
{
throw EvalError({
.msg = hintfmt(s),
.errPos = pos
});
}
LocalNoInlineNoReturn(void throwTypeError(const Pos & pos, const char * s, const Value & v))
{
throw TypeError({
.msg = hintfmt(s, showType(v)),
.errPos = pos
});
}
/* Note: Various places expect the allocated memory to be zeroed. */
[[gnu::always_inline]]
inline void * allocBytes(size_t n)
{
void * p;
#if HAVE_BOEHMGC
p = GC_MALLOC(n);
#else
p = calloc(n, 1);
#endif
if (!p) throw std::bad_alloc();
return p;
}
[[gnu::always_inline]]
Value * EvalState::allocValue()
{
#if HAVE_BOEHMGC
/* We use the boehm batch allocator to speed up allocations of Values (of which there are many).
GC_malloc_many returns a linked list of objects of the given size, where the first word
of each object is also the pointer to the next object in the list. This also means that we
have to explicitly clear the first word of every object we take. */
if (!*valueAllocCache) {
*valueAllocCache = GC_malloc_many(sizeof(Value));
if (!*valueAllocCache) throw std::bad_alloc();
}
/* GC_NEXT is a convenience macro for accessing the first word of an object.
Take the first list item, advance the list to the next item, and clear the next pointer. */
void * p = *valueAllocCache;
*valueAllocCache = GC_NEXT(p);
GC_NEXT(p) = nullptr;
#else
void * p = allocBytes(sizeof(Value));
#endif
nrValues++;
return (Value *) p;
}
[[gnu::always_inline]]
Env & EvalState::allocEnv(size_t size)
{
nrEnvs++;
nrValuesInEnvs += size;
Env * env;
#if HAVE_BOEHMGC
if (size == 1) {
/* see allocValue for explanations. */
if (!*env1AllocCache) {
*env1AllocCache = GC_malloc_many(sizeof(Env) + sizeof(Value *));
if (!*env1AllocCache) throw std::bad_alloc();
}
void * p = *env1AllocCache;
*env1AllocCache = GC_NEXT(p);
GC_NEXT(p) = nullptr;
env = (Env *) p;
} else
#endif
env = (Env *) allocBytes(sizeof(Env) + size * sizeof(Value *));
env->type = Env::Plain;
/* We assume that env->values has been cleared by the allocator; maybeThunk() and lookupVar fromWith expect this. */
return *env;
}
[[gnu::always_inline]]
void EvalState::forceValue(Value & v, const Pos & pos)
{
forceValue(v, [&]() { return pos; });
}
template<typename Callable>
void EvalState::forceValue(Value & v, Callable getPos)
{
if (v.isThunk()) {
Env * env = v.thunk.env;
Expr * expr = v.thunk.expr;
try {
v.mkBlackhole();
//checkInterrupt();
expr->eval(*this, *env, v);
} catch (...) {
v.mkThunk(env, expr);
throw;
}
}
else if (v.isApp())
callFunction(*v.app.left, *v.app.right, v, noPos);
else if (v.isBlackhole())
throwEvalError(getPos(), "infinite recursion encountered");
}
[[gnu::always_inline]]
inline void EvalState::forceAttrs(Value & v, const Pos & pos, std::string_view errorCtx)
{
forceAttrs(v, [&]() { return pos; }, errorCtx);
}
template <typename Callable>
[[gnu::always_inline]]
inline void EvalState::forceAttrs(Value & v, Callable getPos, std::string_view errorCtx)
{
try {
forceValue(v, noPos);
if (v.type() != nAttrs) {
throwTypeError(noPos, "value is %1% while a set was expected", v);
}
} catch (Error & e) {
Pos pos = getPos();
e.addTrace(pos, errorCtx);
throw;
}
}
[[gnu::always_inline]]
inline void EvalState::forceList(Value & v, const Pos & pos, std::string_view errorCtx)
{
try {
forceValue(v, noPos);
if (!v.isList()) {
throwTypeError(noPos, "value is %1% while a list was expected", v);
}
} catch (Error & e) {
e.addTrace(pos, errorCtx);
throw;
}
}
}
|