Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

feat(stdlib): Faster memory allocator #2124

Merged
merged 2 commits into from
Jun 25, 2024
Merged

feat(stdlib): Faster memory allocator #2124

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
390ae04
feat(stdlib): Faster memory allocator
ospencer Jun 16, 2024
a4db786
update contributor doc
ospencer Jun 25, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
34 changes: 0 additions & 34 deletions compiler/test/input/mallocTight.gr
View file
Open in desktop

This file was deleted.

58 changes: 31 additions & 27 deletions compiler/test/runner.re
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -39,7 +39,7 @@ let graindoc_out_file = name =>
let gaindoc_in_file = name =>
Filepath.to_string(Fp.At.(test_gaindoc_dir / (name ++ ".input.gr")));

let compile = (~num_pages=?, ~config_fn=?, ~hook=?, name, prog) => {
let compile = (~num_pages=?, ~max_pages=?, ~config_fn=?, ~hook=?, name, prog) => {
Config.preserve_all_configs(() => {
Config.with_config(
Config.empty,
Expand All @@ -49,11 +49,10 @@ let compile = (~num_pages=?, ~config_fn=?, ~hook=?, name, prog) => {
| None => ()
};
switch (num_pages) {
| Some(pages) =>
Config.initial_memory_pages := pages;
Config.maximum_memory_pages := Some(pages);
| Some(pages) => Config.initial_memory_pages := pages
| None => ()
};
Config.maximum_memory_pages := max_pages;
Config.include_dirs :=
[Filepath.to_string(test_libs_dir), ...Config.include_dirs^];
let outfile = wasmfile(name);
Expand All @@ -63,7 +62,8 @@ let compile = (~num_pages=?, ~config_fn=?, ~hook=?, name, prog) => {
});
};

let compile_file = (~num_pages=?, ~config_fn=?, ~hook=?, filename, outfile) => {
let compile_file =
(~num_pages=?, ~max_pages=?, ~config_fn=?, ~hook=?, filename, outfile) => {
Config.preserve_all_configs(() => {
Config.with_config(
Config.empty,
Expand All @@ -73,11 +73,10 @@ let compile_file = (~num_pages=?, ~config_fn=?, ~hook=?, filename, outfile) => {
| None => ()
};
switch (num_pages) {
| Some(pages) =>
Config.initial_memory_pages := pages;
Config.maximum_memory_pages := Some(pages);
| Some(pages) => Config.initial_memory_pages := pages
| None => ()
};
Config.maximum_memory_pages := max_pages;
Config.include_dirs :=
[Filepath.to_string(test_libs_dir), ...Config.include_dirs^];
compile_file(~is_root_file=true, ~hook?, ~outfile, filename);
Expand Down Expand Up @@ -153,18 +152,7 @@ let open_process = args => {
(code, out, err);
};

let run = (~num_pages=?, ~extra_args=[||], file) => {
let mem_flags =
switch (num_pages) {
| Some(x) => [|
"--initial-memory-pages",
string_of_int(x),
"--maximum-memory-pages",
string_of_int(x),
|]
| None => [||]
};

let run = (~extra_args=[||], file) => {
let stdlib = Option.get(Grain_utils.Config.stdlib_dir^);

let preopen =
Expand All @@ -186,7 +174,6 @@ let run = (~num_pages=?, ~extra_args=[||], file) => {
let cmd =
Array.concat([
[|"grain", "run"|],
mem_flags,
[|"-S", stdlib, "-I", Filepath.to_string(test_libs_dir), preopen|],
[|file|],
extra_args,
Expand Down Expand Up @@ -306,6 +293,7 @@ let makeRunner =
(
test,
~num_pages=?,
~max_pages=?,
~config_fn=?,
~extra_args=?,
~module_header=module_header,
Expand All @@ -315,8 +303,15 @@ let makeRunner =
) => {
test(name, ({expect}) => {
Config.preserve_all_configs(() => {
ignore @@ compile(~num_pages?, ~config_fn?, name, module_header ++ prog);
let (result, _) = run(~num_pages?, ~extra_args?, wasmfile(name));
ignore @@
compile(
~num_pages?,
~max_pages?,
~config_fn?,
name,
module_header ++ prog,
);
let (result, _) = run(~extra_args?, wasmfile(name));
expect.string(result).toEqual(expected);
})
});
Expand All @@ -327,6 +322,7 @@ let makeErrorRunner =
test,
~check_exists=true,
~num_pages=?,
~max_pages=?,
~config_fn=?,
~module_header=module_header,
name,
Expand All @@ -335,8 +331,15 @@ let makeErrorRunner =
) => {
test(name, ({expect}) => {
Config.preserve_all_configs(() => {
ignore @@ compile(~num_pages?, ~config_fn?, name, module_header ++ prog);
let (result, _) = run(~num_pages?, wasmfile(name));
ignore @@
compile(
~num_pages?,
~max_pages?,
~config_fn?,
name,
module_header ++ prog,
);
let (result, _) = run(wasmfile(name));
if (check_exists) {
expect.string(result).toMatch(expected);
} else {
Expand All @@ -347,12 +350,13 @@ let makeErrorRunner =
};

let makeFileRunner =
(test, ~num_pages=?, ~config_fn=?, name, filename, expected) => {
(test, ~num_pages=?, ~max_pages=?, ~config_fn=?, name, filename, expected) => {
test(name, ({expect}) => {
Config.preserve_all_configs(() => {
let infile = grainfile(filename);
let outfile = wasmfile(name);
ignore @@ compile_file(~num_pages?, ~config_fn?, infile, outfile);
ignore @@
compile_file(~num_pages?, ~max_pages?, ~config_fn?, infile, outfile);
let (result, _) = run(outfile);
expect.string(result).toEqual(expected);
})
Expand Down
2 changes: 1 addition & 1 deletion compiler/test/suites/basic_functionality.re
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -377,6 +377,6 @@ describe("basic functionality", ({test, testSkip}) => {
~config_fn=smallestFileConfig,
"smallest_grain_program",
"",
4769,
5165,
);
});
59 changes: 32 additions & 27 deletions compiler/test/suites/gc.re
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -8,24 +8,25 @@ let makeGcProgram = (program, heap_size) => {
from "runtime/malloc" include Malloc
from "runtime/unsafe/memory" include Memory

@disableGC
primitive heapStart = "@heap.start"

@disableGC
let leak = () => {
use WasmI32.{ (+), (-) }
// find current memory pointer, subtract space for two malloc headers + 1 GC header
let offset = Memory.malloc(8n) - 24n
// Calculate how much memory is left
let availableMemory = offset - (Malloc._RESERVED_RUNTIME_SPACE + heapStart())
// Calculate how much memory to leak
let toLeak = availableMemory - %dn
// Memory is not reclaimed due to no gc context
// This will actually leak 16 extra bytes because of the headers
Memory.malloc(toLeak - 16n);
void
@unsafe
let _ = {
use WasmI32.{(*), (-), (==)}
// Leak all available memory
// The first call to malloc ensures it has been initialized
Malloc.malloc(8n)
Malloc.leakAll()
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I don't like leakAll being a public API on malloc

// Next allocation will grow the memory by 1 page (64kib)
// We'll manually leak all memory except what should be reserved for the test
// Round reserved memory to nearest block size
let reserved = %dn
// If only one unit is requested, the allocator will include it in our next malloc,
// so we request 2 instead
let reserved = if (reserved == 1n) 2n else reserved
// one page - 2 malloc headers - 1 gc header - extra morecore unit - reserved space
let toLeak = 65536n - 16n - 8n - 64n - reserved * 64n
Memory.malloc(toLeak)
}
leak();

%s
|},
heap_size,
Expand All @@ -43,6 +44,7 @@ describe("garbage collection", ({test, testSkip}) => {
let assertRunGC = (name, heapSize, prog, expected) =>
makeRunner(
~num_pages=1,
~max_pages=2,
test_or_skip,
name,
makeGcProgram(prog, heapSize),
Expand All @@ -52,38 +54,42 @@ describe("garbage collection", ({test, testSkip}) => {
makeErrorRunner(
test_or_skip,
~num_pages=1,
~max_pages=2,
name,
makeGcProgram(prog, heapSize),
expected,
);

// oom tests
// The allocator will use 2 units for the first allocation and then oom
assertRunGCError(
"oomgc1",
48,
2,
"(1, (3, 4))",
"Maximum memory size exceeded",
);
assertRunGC("oomgc2", 64, "(1, (3, 4))", "");
assertRunGC("oomgc3", 32, "(3, 4)", "");
// This requires only 2 units, but if only two are requested they would be
// used by the first allocation
assertRunGC("oomgc2", 3, "(1, (3, 4))", "");
assertRunGC("oomgc3", 1, "(3, 4)", "");

// gc tests
assertRunGC(
"gc1",
160,
5,
"let f = (() => (1, 2));\n {\n f();\n f();\n f();\n f()\n }",
"",
);
/* https://github.com/grain-lang/grain/issues/774 */
assertRunGC(
"gc3",
1024,
17,
"let foo = (s: String) => void\nlet printBool = (b: Bool) => foo(if (b) \"true\" else \"false\")\n\nlet b = true\nfor (let mut i=0; i<100000; i += 1) {\n printBool(true)\n}",
"",
);
assertRunGCError(
"fib_gc_err",
256,
5,
{|
let fib = x => {
let rec fib_help = (n, acc) => {
Expand All @@ -102,7 +108,7 @@ describe("garbage collection", ({test, testSkip}) => {
);
assertRunGC(
"fib_gc",
512,
9,
{|
let fib = x => {
let rec fib_help = (n, acc) => {
Expand All @@ -121,7 +127,7 @@ describe("garbage collection", ({test, testSkip}) => {
);
assertRunGC(
"loop_gc",
256,
5,
{|
for (let mut i = 0; i < 512; i += 1) {
let string = "string"
Expand All @@ -134,7 +140,7 @@ describe("garbage collection", ({test, testSkip}) => {
);
assertRunGC(
"long_lists",
20000,
350,
{|
from "list" include List
use List.*
Expand Down Expand Up @@ -162,7 +168,6 @@ describe("garbage collection", ({test, testSkip}) => {
|},
"true\n",
);
assertFileRun("malloc_tight", "mallocTight", "");
assertFileRun("memory_grow1", "memoryGrow", "1000000000000\n");
assertMemoryLimitedFileRun(
"loop_memory_reclaim",
Expand Down
8 changes: 3 additions & 5 deletions docs/contributor/memory_management.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -6,7 +6,7 @@ We ultimately aim to replace Grain's bespoke memory management with the WebAssem

## Memory Allocator

Grain uses a [memory allocator](https://github.com/grain-lang/grain/blob/main/stdlib/runtime/malloc.gr) derived from the `malloc`/`free` example given in Kernighan and Ritchie's ["The C Programming Language"](https://kremlin.cc/k&r.pdf) (K&R C), pages 185-188 (PDF page 199). This module exports the following values:
More documentation about Grain's [memory allocator](https://github.com/grain-lang/grain/blob/main/stdlib/runtime/malloc.gr) can be found in that module. It exports the following values:

```grain
/**
Expand All @@ -31,11 +31,9 @@ export let malloc: (nbytes: WasmI32) -> WasmI32
export let free = (ap: WasmI32) => Void

/**
* Returns the current free list pointer (used for debugging)
*
* @returns The free list pointer
* Leaks all memory in all free lists; used for testing.
*/
export let getFreePtr = () => WasmI32
export let leakAll = () => Void
```

These functions should be familiar to programmers who have used `malloc` and `free` in C (and C-like languages). For further reading, refer to this Wikipedia page: [C dynamic memory allocation](https://en.wikipedia.org/wiki/C_dynamic_memory_allocation). The semantics of these functions align near-identically with those of C's corresponding functions.
Expand Down
Loading
Loading