feat: Custom memory page size (#22)

2 files changed, 222 insertions, 0 deletions

diff --git a/crates/wasm-testsuite/tests/proposals/custom-page-sizes/custom-page-sizes-invalid.wast b/crates/wasm-testsuite/tests/proposals/custom-page-sizes/custom-page-sizes-invalid.wast
new file mode 100644
index 0000000..150f58b
--- /dev/null
+++ b/crates/wasm-testsuite/tests/proposals/custom-page-sizes/custom-page-sizes-invalid.wast
@@ -0,0 +1,112 @@
+;; from https://github.com/WebAssembly/custom-page-sizes/blob/main/test/core/custom-page-sizes/custom-page-sizes-invalid.wast
+
+;; Page size that is not a power of two.
+(assert_malformed
+  (module quote "(memory 0 (pagesize 3))")
+  "invalid custom page size"
+)
+
+;; Power-of-two page sizes that are not 1 or 64KiB.
+(assert_invalid
+  (module (memory 0 (pagesize 2)))
+  "invalid custom page size"
+)
+(assert_invalid
+  (module (memory 0 (pagesize 4)))
+  "invalid custom page size"
+)
+(assert_invalid
+  (module (memory 0 (pagesize 8)))
+  "invalid custom page size"
+)
+(assert_invalid
+  (module (memory 0 (pagesize 16)))
+  "invalid custom page size"
+)
+(assert_invalid
+  (module (memory 0 (pagesize 32)))
+  "invalid custom page size"
+)
+(assert_invalid
+  (module (memory 0 (pagesize 64)))
+  "invalid custom page size"
+)
+(assert_invalid
+  (module (memory 0 (pagesize 128)))
+  "invalid custom page size"
+)
+(assert_invalid
+  (module (memory 0 (pagesize 256)))
+  "invalid custom page size"
+)
+(assert_invalid
+  (module (memory 0 (pagesize 512)))
+  "invalid custom page size"
+)
+(assert_invalid
+  (module (memory 0 (pagesize 1024)))
+  "invalid custom page size"
+)
+(assert_invalid
+  (module (memory 0 (pagesize 2048)))
+  "invalid custom page size"
+)
+(assert_invalid
+  (module (memory 0 (pagesize 4096)))
+  "invalid custom page size"
+)
+(assert_invalid
+  (module (memory 0 (pagesize 8192)))
+  "invalid custom page size"
+)
+(assert_invalid
+  (module (memory 0 (pagesize 16384)))
+  "invalid custom page size"
+)
+(assert_invalid
+  (module (memory 0 (pagesize 32768)))
+  "invalid custom page size"
+)
+
+;; Power-of-two page size that is larger than 64KiB.
+(assert_invalid
+  (module (memory 0 (pagesize 0x20000)))
+  "invalid custom page size"
+)
+
+;; Power of two page size that cannot fit in a u64 to exercise checks against
+;; shift overflow.
+(assert_malformed
+  (module binary
+    "\00asm" "\01\00\00\00"
+    "\05\04\01"                ;; Memory section
+
+    ;; memory 0
+    "\08"                      ;; flags w/ custom page size
+    "\00"                      ;; minimum = 0
+    "\41"                      ;; pagesize = 2**65
+  )
+  "invalid custom page size"
+)
+
+;; Importing a memory with the wrong page size.
+
+(module $m
+  (memory (export "small-pages-memory") 0 (pagesize 1))
+  (memory (export "large-pages-memory") 0 (pagesize 65536))
+)
+(register "m" $m)
+
+(assert_unlinkable
+  (module
+    (memory (import "m" "small-pages-memory") 0 (pagesize 65536))
+  )
+  "incompatible import type"
+)
+
+(assert_unlinkable
+  (module
+    (memory (import "m" "large-pages-memory") 0 (pagesize 1))
+  )
+  "incompatible import type"
+)
diff --git a/crates/wasm-testsuite/tests/proposals/custom-page-sizes/custom-page-sizes.wast b/crates/wasm-testsuite/tests/proposals/custom-page-sizes/custom-page-sizes.wast
new file mode 100644
index 0000000..f59d52b
--- /dev/null
+++ b/crates/wasm-testsuite/tests/proposals/custom-page-sizes/custom-page-sizes.wast
@@ -0,0 +1,110 @@
+;; from https://github.com/WebAssembly/custom-page-sizes/blob/main/test/core/custom-page-sizes/custom-page-sizes.wast
+
+;; Check all the valid custom page sizes.
+(module (memory 1 (pagesize 1)))
+(module (memory 1 (pagesize 65536)))
+
+;; Check them all again with maximums specified.
+(module (memory 1 2 (pagesize 1)))
+(module (memory 1 2 (pagesize 65536)))
+
+;; Check the behavior of memories with page size 1.
+(module
+  (memory 0 (pagesize 1))
+  (func (export "size") (result i32)
+    memory.size
+  )
+  (func (export "grow") (param i32) (result i32)
+    (memory.grow (local.get 0))
+  )
+  (func (export "load") (param i32) (result i32)
+    (i32.load8_u (local.get 0))
+  )
+  (func (export "store") (param i32 i32)
+    (i32.store8 (local.get 0) (local.get 1))
+  )
+)
+
+(assert_return (invoke "size") (i32.const 0))
+(assert_trap (invoke "load" (i32.const 0)) "out of bounds memory access")
+
+(assert_return (invoke "grow" (i32.const 65536)) (i32.const 0))
+(assert_return (invoke "size") (i32.const 65536))
+(assert_return (invoke "load" (i32.const 65535)) (i32.const 0))
+(assert_return (invoke "store" (i32.const 65535) (i32.const 1)))
+(assert_return (invoke "load" (i32.const 65535)) (i32.const 1))
+(assert_trap (invoke "load" (i32.const 65536)) "out of bounds memory access")
+
+(assert_return (invoke "grow" (i32.const 65536)) (i32.const 65536))
+(assert_return (invoke "size") (i32.const 131072))
+(assert_return (invoke "load" (i32.const 131071)) (i32.const 0))
+(assert_return (invoke "store" (i32.const 131071) (i32.const 1)))
+(assert_return (invoke "load" (i32.const 131071)) (i32.const 1))
+(assert_trap (invoke "load" (i32.const 131072)) "out of bounds memory access")
+
+;; Although smaller page sizes let us get to memories larger than 2**16 pages,
+;; we can't do that with the default page size, even if we explicitly state it
+;; as a custom page size.
+(module
+  (memory 0 (pagesize 65536))
+  (func (export "size") (result i32)
+    memory.size
+  )
+  (func (export "grow") (param i32) (result i32)
+    (memory.grow (local.get 0))
+  )
+)
+(assert_return (invoke "size") (i32.const 0))
+(assert_return (invoke "grow" (i32.const 65537)) (i32.const -1))
+(assert_return (invoke "size") (i32.const 0))
+
+;; Can copy between memories of different page sizes.
+(module
+  (memory $small 10 (pagesize 1))
+  (memory $large 1 (pagesize 65536))
+
+  (data (memory $small) (i32.const 0) "\11\22\33\44")
+  (data (memory $large) (i32.const 0) "\55\66\77\88")
+
+  (func (export "copy-small-to-large") (param i32 i32 i32)
+    (memory.copy $large $small (local.get 0) (local.get 1) (local.get 2))
+  )
+
+  (func (export "copy-large-to-small") (param i32 i32 i32)
+    (memory.copy $small $large (local.get 0) (local.get 1) (local.get 2))
+  )
+
+  (func (export "load8-small") (param i32) (result i32)
+    (i32.load8_u $small (local.get 0))
+  )
+
+  (func (export "load8-large") (param i32) (result i32)
+    (i32.load8_u $large (local.get 0))
+  )
+)
+
+(assert_return (invoke "copy-small-to-large" (i32.const 6) (i32.const 0) (i32.const 2)))
+(assert_return (invoke "load8-large" (i32.const 6)) (i32.const 0x11))
+(assert_return (invoke "load8-large" (i32.const 7)) (i32.const 0x22))
+
+(assert_return (invoke "copy-large-to-small" (i32.const 4) (i32.const 1) (i32.const 3)))
+(assert_return (invoke "load8-small" (i32.const 4)) (i32.const 0x66))
+(assert_return (invoke "load8-small" (i32.const 5)) (i32.const 0x77))
+(assert_return (invoke "load8-small" (i32.const 6)) (i32.const 0x88))
+
+;; Can link together modules that export and import memories with custom page
+;; sizes.
+
+(module $m
+  (memory (export "small-pages-memory") 0 (pagesize 1))
+  (memory (export "large-pages-memory") 0 (pagesize 65536))
+)
+(register "m" $m)
+
+(module
+  (memory (import "m" "small-pages-memory") 0 (pagesize 1))
+)
+
+(module
+  (memory (import "m" "large-pages-memory") 0 (pagesize 65536))
+)