fix: Backport static memory fixes made in #1559

src/compiler.ts

@@ -194,7 +194,8 @@ import {
   writeF64,
   uniqueMap,
   isPowerOf2,
-  v128_zero
+  v128_zero,
+  readI32
 } from "./util";
 
 /** Compiler options. */
@@ -1844,26 +1845,23 @@ export class Compiler extends DiagnosticEmitter {
     var memoryOffset = i64_align(this.memoryOffset, alignment);
     var segment = new MemorySegment(buffer, memoryOffset);
     this.memorySegments.push(segment);
-    this.memoryOffset = i64_add(memoryOffset, i64_new(buffer.length, 0));
+    this.memoryOffset = i64_add(memoryOffset, i64_new(buffer.length));
     return segment;
   }
 
   /** Adds a static memory segment representing a runtime object. */
   addRuntimeMemorySegment(buffer: Uint8Array): MemorySegment {
-    // Runtime objects imply a full BLOCK and OBJECT header, see rt/common.ts
-    // ((memoryOffset + sizeof_usize + AL_MASK) & ~AL_MASK) - sizeof_usize
-    var usizeSize = this.options.usizeType.byteSize;
-    var memoryOffset = i64_sub(i64_align(i64_add(this.memoryOffset, i64_new(usizeSize)), 16), i64_new(usizeSize));
+    var memoryOffset = this.program.computeBlockStart64(this.memoryOffset);
     var segment = new MemorySegment(buffer, memoryOffset);
     this.memorySegments.push(segment);
-    this.memoryOffset = i64_add(memoryOffset, i64_new(buffer.length, 0));
+    this.memoryOffset = i64_add(memoryOffset, i64_new(buffer.length));
     return segment;
   }
 
   /** Ensures that a string exists in static memory and returns a pointer to it. Deduplicates. */
   ensureStaticString(stringValue: string): ExpressionRef {
     var program = this.program;
-    var rtHeaderSize = program.runtimeHeaderSize;
+    var totalOverhead = program.totalOverhead;
     var stringInstance = assert(program.stringInstance);
     var stringSegment: MemorySegment;
     var segments = this.stringSegments;
@@ -1873,12 +1871,12 @@ export class Compiler extends DiagnosticEmitter {
       let len = stringValue.length;
       let buf = stringInstance.createBuffer(len << 1);
       for (let i = 0; i < len; ++i) {
-        writeI16(stringValue.charCodeAt(i), buf, rtHeaderSize + (i << 1));
+        writeI16(stringValue.charCodeAt(i), buf, totalOverhead + (i << 1));
       }
       stringSegment = this.addRuntimeMemorySegment(buf);
       segments.set(stringValue, stringSegment);
     }
-    var ptr = i64_add(stringSegment.offset, i64_new(rtHeaderSize));
+    var ptr = i64_add(stringSegment.offset, i64_new(totalOverhead));
     this.currentType = stringInstance.type;
     if (this.options.isWasm64) {
       return this.module.i64(i64_low(ptr), i64_high(ptr));
@@ -1971,19 +1969,18 @@ export class Compiler extends DiagnosticEmitter {
     var arrayBufferInstance = program.arrayBufferInstance;
     var buf = arrayBufferInstance.createBuffer(values.length * elementType.byteSize);
     this.program.OBJECTInstance.writeField("rtId", id, buf, 0); // use specified rtId
-    assert(this.writeStaticBuffer(buf, program.runtimeHeaderSize, elementType, values) == buf.length);
+    this.writeStaticBuffer(buf, program.totalOverhead, elementType, values);
     return this.addRuntimeMemorySegment(buf);
   }
 
   /** Adds an array header to static memory and returns the created segment. */
   private addStaticArrayHeader(elementType: Type, bufferSegment: MemorySegment): MemorySegment {
     var program = this.program;
-    var runtimeHeaderSize = program.runtimeHeaderSize;
     var arrayPrototype = assert(program.arrayPrototype);
     var arrayInstance = assert(this.resolver.resolveClass(arrayPrototype, [ elementType ]));
-    var bufferLength = bufferSegment.buffer.length - runtimeHeaderSize;
+    var bufferLength = readI32(bufferSegment.buffer, program.OBJECTInstance.offsetof("rtSize"));
     var arrayLength = i32(bufferLength / elementType.byteSize);
-    var bufferAddress = i64_add(bufferSegment.offset, i64_new(runtimeHeaderSize));
+    var bufferAddress = i64_add(bufferSegment.offset, i64_new(program.totalOverhead));
 
     var buf = arrayInstance.createBuffer();
     assert(arrayInstance.writeField("buffer", bufferAddress, buf));
@@ -2016,7 +2013,7 @@ export class Compiler extends DiagnosticEmitter {
       assert(rtInstance.writeField("_env", 0, buf));
       instance.memorySegment = memorySegment = this.addRuntimeMemorySegment(buf);
     }
-    return i64_add(memorySegment.offset, i64_new(program.runtimeHeaderSize));
+    return i64_add(memorySegment.offset, i64_new(program.totalOverhead));
   }
 
   // === Statements ===============================================================================
@@ -8699,15 +8696,15 @@ export class Compiler extends DiagnosticEmitter {
       flow.freeTempLocal(tempThis);
       flow.freeTempLocal(tempDataStart);
 
-      let runtimeHeaderSize = program.runtimeHeaderSize;
+      let totalOverhead = program.totalOverhead;
       let bufferSegment = this.addStaticBuffer(elementType, values);
-      let bufferAddress = i64_add(bufferSegment.offset, i64_new(runtimeHeaderSize));
+      let bufferAddress = i64_add(bufferSegment.offset, i64_new(totalOverhead));
 
       // make both the buffer and array header static if assigned to a global. this can't be done
       // if inside of a function because each invocation must create a new array reference then.
       if (constraints & Constraints.PREFER_STATIC) {
         let arraySegment = this.addStaticArrayHeader(elementType, bufferSegment);
-        let arrayAddress = i64_add(arraySegment.offset, i64_new(runtimeHeaderSize));
+        let arrayAddress = i64_add(arraySegment.offset, i64_new(totalOverhead));
         this.currentType = arrayType;
         return program.options.isWasm64
           ? this.module.i64(i64_low(arrayAddress), i64_high(arrayAddress))
@@ -8872,7 +8869,7 @@ export class Compiler extends DiagnosticEmitter {
       flow.freeTempLocal(tempThis);
 
       let bufferSegment = this.addStaticBuffer(elementType, values, arrayInstance.id);
-      let bufferAddress = i64_add(bufferSegment.offset, i64_new(program.runtimeHeaderSize));
+      let bufferAddress = i64_add(bufferSegment.offset, i64_new(program.totalOverhead));
 
       // return the static buffer directly if assigned to a global
       if (constraints & Constraints.PREFER_STATIC) {

src/program.ts

@@ -148,6 +148,10 @@ import {
   BuiltinNames
 } from "./builtins";
 
+// Memory manager constants
+const AL_SIZE = 16;
+const AL_MASK = AL_SIZE - 1;
+
 /** Represents a yet unresolved `import`. */
 class QueuedImport {
   constructor(
@@ -769,23 +773,58 @@ export class Program extends DiagnosticEmitter {
     return null;
   }
 
-  /** Gets the size of a runtime header. */
-  get runtimeHeaderSize(): i32 {
-    var cached = this._runtimeHeaderSize;
-    if (!cached) {
-      // see: rt/common.ts
-      var blockOverhead = this.BLOCKInstance.nextMemoryOffset;
-      var totalOverhead = this.OBJECTInstance.nextMemoryOffset;
-      const AL_SIZE = 16;
-      const AL_MASK = AL_SIZE - 1;
-      var objectOverhead = (totalOverhead - blockOverhead + AL_MASK) & ~AL_MASK;
-      var headerSize = blockOverhead + objectOverhead;
-      assert(headerSize == 20);
-      this._runtimeHeaderSize = cached = headerSize;
+  /** Gets the overhead of a memory manager block. */
+  get blockOverhead(): i32 {
+    // BLOCK | data...
+    //       ^ 16b alignment
+    return this.BLOCKInstance.nextMemoryOffset;
+  }
+
+  /** Gets the overhead of a managed object, excl. block overhead, incl. alignment. */
+  get objectOverhead(): i32 {
+    // OBJECT+align | data...
+    //        └ 0 ┘ ^ 16b alignment
+    return (this.OBJECTInstance.nextMemoryOffset - this.blockOverhead + AL_MASK) & ~AL_MASK;
+  }
+
+  /** Gets the total overhead of a managed object, incl. block overhead. */
+  get totalOverhead(): i32 {
+    // BLOCK | OBJECT+align | data...
+    // └     = TOTAL      ┘ ^ 16b alignment
+    return this.blockOverhead + this.objectOverhead;
+  }
+
+  /** Computes the next properly aligned offset of a memory manager block, given the current bump offset. */
+  computeBlockStart(currentOffset: i32): i32 {
+    var blockOverhead = this.blockOverhead;
+    return ((currentOffset + blockOverhead + AL_MASK) & ~AL_MASK) - blockOverhead;
+  }
+
+  /** Computes the next properly aligned offset of a memory manager block, given the current bump offset. */
+  computeBlockStart64(currentOffset: i64): i64 {
+    var blockOverhead = i64_new(this.blockOverhead);
+    return i64_sub(i64_align(i64_add(currentOffset, blockOverhead), AL_SIZE), blockOverhead);
+  }
+
+  /** Computes the size of a memory manager block, excl. block overhead. */
+  computeBlockSize(payloadSize: i32, isManaged: bool): i32 {
+    // see: std/rt/tlsf.ts, computeSize; becomes mmInfo
+    if (isManaged) payloadSize += this.objectOverhead;
+    // we know that payload must be aligned, and that block sizes must be chosen
+    // so that blocks are adjacent with the next payload aligned. hence, block
+    // size is payloadSize rounded up to where the next block would start:
+    var blockSize = this.computeBlockStart(payloadSize);
+    // make sure that block size is valid according to TLSF requirements
+    var blockOverhead = this.blockOverhead;
+    var blockMinsize = ((3 * this.options.usizeType.byteSize + blockOverhead + AL_MASK) & ~AL_MASK) - blockOverhead;
+    if (blockSize < blockMinsize) blockSize = blockMinsize;
+    const blockMaxsize = 1 << 30; // 1 << (FL_BITS + SB_BITS - 1), exclusive
+    const tagsMask = 3;
+    if (blockSize >= blockMaxsize || (blockSize & tagsMask) != 0) {
+      throw new Error("invalid block size");
     }
-    return cached;
+    return blockSize;
   }
-  private _runtimeHeaderSize: u32 = 0;
 
   /** Creates a native variable declaration. */
   makeNativeVariableDeclaration(
@@ -4299,22 +4338,22 @@ export class Class extends TypedElement {
 
   /** Creates a buffer suitable to hold a runtime instance of this class. */
   createBuffer(overhead: i32 = 0): Uint8Array {
-    var size = this.nextMemoryOffset + overhead;
-    var buffer = new Uint8Array(this.program.runtimeHeaderSize + size);
-    assert(!this.program.options.isWasm64); // TODO: WASM64, mmInfo is usize
-    // see: std/assembly/rt/common.ts
-    assert(size < (1 << 28));      // 1 bit BUFFERED + 3 bits color
-    var OBJECT = this.program.OBJECTInstance;
-    OBJECT.writeField("mmInfo", size, buffer, 0);
+    var program = this.program;
+    var payloadSize = this.nextMemoryOffset + overhead;
+    var blockSize = program.computeBlockSize(payloadSize, true); // excl. overhead
+    var totalSize = program.blockOverhead + blockSize;
+    var buffer = new Uint8Array(totalSize);
+    var OBJECT = program.OBJECTInstance;
+    OBJECT.writeField("mmInfo", blockSize, buffer, 0);
     OBJECT.writeField("gcInfo", 1, buffer, 0); // RC = 1
     OBJECT.writeField("gcInfo2", 0, buffer, 0);
     OBJECT.writeField("rtId", this.id, buffer, 0);
-    OBJECT.writeField("rtSize", size, buffer, 0);
+    OBJECT.writeField("rtSize", payloadSize, buffer, 0);
     return buffer;
   }
 
   /** Writes a field value to a buffer and returns the number of bytes written. */
-  writeField<T>(name: string, value: T, buffer: Uint8Array, baseOffset: i32 = this.program.runtimeHeaderSize): i32 {
+  writeField<T>(name: string, value: T, buffer: Uint8Array, baseOffset: i32 = this.program.totalOverhead): i32 {
     var element = this.lookupInSelf(name);
     if (element !== null && element.kind == ElementKind.FIELD) {
       let fieldInstance = <Field>element;

tests/compiler/abi.optimized.wat

@@ -1,7 +1,7 @@
 (module
  (type $none_=>_i32 (func (result i32)))
  (memory $0 1)
- (data (i32.const 1036) "\0c\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00\0c\00\00\00a\00b\00i\00.\00t\00s")
+ (data (i32.const 1036) "\1c\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00\0c\00\00\00a\00b\00i\00.\00t\00s")
  (export "memory" (memory $0))
  (export "exported" (func $abi/exported))
  (export "exportedExported" (func $abi/exported))

tests/compiler/abi.untouched.wat

@@ -4,7 +4,7 @@
  (type $i32_i32_i32_i32_=>_none (func (param i32 i32 i32 i32)))
  (import "env" "abort" (func $~lib/builtins/abort (param i32 i32 i32 i32)))
  (memory $0 1)
- (data (i32.const 12) "\0c\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00\0c\00\00\00a\00b\00i\00.\00t\00s\00")
+ (data (i32.const 12) "\1c\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00\0c\00\00\00a\00b\00i\00.\00t\00s\00")
  (table $0 1 funcref)
  (global $abi/condition (mut i32) (i32.const 0))
  (global $abi/y (mut i32) (i32.const 0))

tests/compiler/assert-nonnull.optimized.wat

@@ -4,11 +4,11 @@
  (type $i32_i32_i32_i32_=>_none (func (param i32 i32 i32 i32)))
  (import "env" "abort" (func $~lib/builtins/abort (param i32 i32 i32 i32)))
  (memory $0 1)
- (data (i32.const 1036) "\1e\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00\1e\00\00\00u\00n\00e\00x\00p\00e\00c\00t\00e\00d\00 \00n\00u\00l\00l")
- (data (i32.const 1100) "\"\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00\"\00\00\00a\00s\00s\00e\00r\00t\00-\00n\00o\00n\00n\00u\00l\00l\00.\00t\00s")
- (data (i32.const 1164) "$\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00$\00\00\00I\00n\00d\00e\00x\00 \00o\00u\00t\00 \00o\00f\00 \00r\00a\00n\00g\00e")
- (data (i32.const 1228) "\1a\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00\1a\00\00\00~\00l\00i\00b\00/\00a\00r\00r\00a\00y\00.\00t\00s")
- (data (i32.const 1276) "^\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00^\00\00\00E\00l\00e\00m\00e\00n\00t\00 \00t\00y\00p\00e\00 \00m\00u\00s\00t\00 \00b\00e\00 \00n\00u\00l\00l\00a\00b\00l\00e\00 \00i\00f\00 \00a\00r\00r\00a\00y\00 \00i\00s\00 \00h\00o\00l\00e\00y")
+ (data (i32.const 1036) "<\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00\1e\00\00\00u\00n\00e\00x\00p\00e\00c\00t\00e\00d\00 \00n\00u\00l\00l")
+ (data (i32.const 1100) "<\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00\"\00\00\00a\00s\00s\00e\00r\00t\00-\00n\00o\00n\00n\00u\00l\00l\00.\00t\00s")
+ (data (i32.const 1164) "<\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00$\00\00\00I\00n\00d\00e\00x\00 \00o\00u\00t\00 \00o\00f\00 \00r\00a\00n\00g\00e")
+ (data (i32.const 1228) ",\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00\1a\00\00\00~\00l\00i\00b\00/\00a\00r\00r\00a\00y\00.\00t\00s")
+ (data (i32.const 1276) "|\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00^\00\00\00E\00l\00e\00m\00e\00n\00t\00 \00t\00y\00p\00e\00 \00m\00u\00s\00t\00 \00b\00e\00 \00n\00u\00l\00l\00a\00b\00l\00e\00 \00i\00f\00 \00a\00r\00r\00a\00y\00 \00i\00s\00 \00h\00o\00l\00e\00y")
  (table $0 1 funcref)
  (export "memory" (memory $0))
  (export "testVar" (func $assert-nonnull/testVar))

tests/compiler/assert-nonnull.untouched.wat

@@ -6,11 +6,11 @@
  (type $i32_i32_i32_i32_=>_none (func (param i32 i32 i32 i32)))
  (import "env" "abort" (func $~lib/builtins/abort (param i32 i32 i32 i32)))
  (memory $0 1)
- (data (i32.const 12) "\1e\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00\1e\00\00\00u\00n\00e\00x\00p\00e\00c\00t\00e\00d\00 \00n\00u\00l\00l\00")
- (data (i32.const 76) "\"\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00\"\00\00\00a\00s\00s\00e\00r\00t\00-\00n\00o\00n\00n\00u\00l\00l\00.\00t\00s\00")
- (data (i32.const 140) "$\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00$\00\00\00I\00n\00d\00e\00x\00 \00o\00u\00t\00 \00o\00f\00 \00r\00a\00n\00g\00e\00")
- (data (i32.const 204) "\1a\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00\1a\00\00\00~\00l\00i\00b\00/\00a\00r\00r\00a\00y\00.\00t\00s\00")
- (data (i32.const 252) "^\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00^\00\00\00E\00l\00e\00m\00e\00n\00t\00 \00t\00y\00p\00e\00 \00m\00u\00s\00t\00 \00b\00e\00 \00n\00u\00l\00l\00a\00b\00l\00e\00 \00i\00f\00 \00a\00r\00r\00a\00y\00 \00i\00s\00 \00h\00o\00l\00e\00y\00")
+ (data (i32.const 12) "<\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00\1e\00\00\00u\00n\00e\00x\00p\00e\00c\00t\00e\00d\00 \00n\00u\00l\00l\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00")
+ (data (i32.const 76) "<\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00\"\00\00\00a\00s\00s\00e\00r\00t\00-\00n\00o\00n\00n\00u\00l\00l\00.\00t\00s\00\00\00\00\00\00\00\00\00\00\00")
+ (data (i32.const 140) "<\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00$\00\00\00I\00n\00d\00e\00x\00 \00o\00u\00t\00 \00o\00f\00 \00r\00a\00n\00g\00e\00\00\00\00\00\00\00\00\00")
+ (data (i32.const 204) ",\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00\1a\00\00\00~\00l\00i\00b\00/\00a\00r\00r\00a\00y\00.\00t\00s\00\00\00")
+ (data (i32.const 252) "|\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00^\00\00\00E\00l\00e\00m\00e\00n\00t\00 \00t\00y\00p\00e\00 \00m\00u\00s\00t\00 \00b\00e\00 \00n\00u\00l\00l\00a\00b\00l\00e\00 \00i\00f\00 \00a\00r\00r\00a\00y\00 \00i\00s\00 \00h\00o\00l\00e\00y\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00")
  (table $0 1 funcref)
  (global $~argumentsLength (mut i32) (i32.const 0))
  (export "memory" (memory $0))

tests/compiler/bool.optimized.wat

@@ -1,5 +1,5 @@
 (module
  (memory $0 1)
- (data (i32.const 1036) "\0e\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00\0e\00\00\00b\00o\00o\00l\00.\00t\00s")
+ (data (i32.const 1036) ",\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00\0e\00\00\00b\00o\00o\00l\00.\00t\00s")
  (export "memory" (memory $0))
 )

tests/compiler/bool.untouched.wat

@@ -3,7 +3,7 @@
  (type $i32_i32_i32_i32_=>_none (func (param i32 i32 i32 i32)))
  (import "env" "abort" (func $~lib/builtins/abort (param i32 i32 i32 i32)))
  (memory $0 1)
- (data (i32.const 12) "\0e\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00\0e\00\00\00b\00o\00o\00l\00.\00t\00s\00")
+ (data (i32.const 12) ",\00\00\00\01\00\00\00\00\00\00\00\01\00\00\00\0e\00\00\00b\00o\00o\00l\00.\00t\00s\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00")
  (table $0 1 funcref)
  (global $bool/i (mut i32) (i32.const 2))
  (global $bool/I (mut i64) (i64.const 2))