ensure meta datas are alignment in linear memory

web-devkits · Sep 27, 2023 · 28f759c · 28f759c
1 parent da83064
commit 28f759c
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Showing 3 changed files with 5 additions and 3 deletions.
diff --git a/src/backend/binaryen/memory.ts b/src/backend/binaryen/memory.ts
@@ -54,7 +54,7 @@ export function initGlobalOffset(module: binaryen.Module) {
     );
 }
 
-export const LinearMemoryAlign = 4;
+export const memoryAlignment = 4;
 
 export function initDefaultMemory(
     module: binaryen.Module,

diff --git a/src/backend/binaryen/utils.ts b/src/backend/binaryen/utils.ts
@@ -42,7 +42,7 @@ import {
 } from '../../semantics/value.js';
 import { ObjectDescriptionType } from '../../semantics/runtime.js';
 import { getConfig } from '../../../config/config_mgr.js';
-import { LinearMemoryAlign } from './memory.js';
+import { memoryAlignment } from './memory.js';
 
 /** typeof an any type object */
 export const enum DynType {
@@ -1634,7 +1634,7 @@ export function getFieldFromMetaByOffset(
     meta: binaryen.ExpressionRef,
     offset: number,
 ) {
-    return module.i32.load(offset, LinearMemoryAlign, meta);
+    return module.i32.load(offset, memoryAlignment, meta);
 }
 
 export interface SourceMapLoc {

diff --git a/src/backend/index.ts b/src/backend/index.ts
@@ -4,6 +4,7 @@
  */
 
 import { ParserContext } from '../frontend.js';
+import { memoryAlignment } from './binaryen/memory.js';
 import { utf16ToUtf8 } from './binaryen/utils.js';
 export { ParserContext } from '../frontend.js';
 
@@ -38,6 +39,7 @@ export class DataSegmentContext {
     }
 
     addData(data: Uint8Array) {
+        this.currentOffset += (memoryAlignment - 1) & ~(memoryAlignment - 1);
         /* there is no efficient approach to cache the data buffer,
             currently we don't cache it */
         const offset = this.currentOffset;