Merge pull request #35 from dylibso/fix-memory-grow-and-size

Fix memory.grow and memory.size
dylibso · Oct 13, 2023 · 17245b4 · 17245b4
2 parents 5d9cc17 + a5e75ac
commit 17245b4
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Showing 4 changed files with 25 additions and 13 deletions.
diff --git a/runtime/src/main/java/com/dylibso/chicory/runtime/Machine.java b/runtime/src/main/java/com/dylibso/chicory/runtime/Machine.java
@@ -344,7 +344,10 @@ void eval(List<Instruction> code) throws ChicoryException {
                         }
                     case MEMORY_GROW:
                         {
-                            instance.getMemory().grow();
+                            var size = stack.pop().asInt();
+                            var nPages = instance.getMemory().grow(size);
+                            // TODO add -1 to stack if memory is exhausted
+                            stack.push(Value.i32(nPages));
                             break;
                         }
                     case I32_STORE8:
@@ -364,7 +367,7 @@ void eval(List<Instruction> code) throws ChicoryException {
                         }
                     case MEMORY_SIZE:
                         {
-                            var sz = instance.getMemory().getInitialSize();
+                            var sz = instance.getMemory().getSize();
                             this.stack.push(Value.i32(sz));
                             break;
                         }

diff --git a/runtime/src/main/java/com/dylibso/chicory/runtime/Memory.java b/runtime/src/main/java/com/dylibso/chicory/runtime/Memory.java
@@ -31,18 +31,27 @@ public Memory(MemoryLimits limits, DataSegment[] dataSegments) {
         this.reinstantiate();
     }
 
-    public void grow() {
+    /**
+     * Gets the size of the memory in number of pages
+     */
+    public int getSize() {
+        return nPages;
+    }
+
+    public int grow(int size) {
+        int numPages = this.nPages + size;
         // TODO if max is null then we just let it grow as much as it wants?
-        if (limits.getMaximum() != null && this.nPages > limits.getMaximum())
+        if (limits.getMaximum() != null && numPages >= limits.getMaximum())
             throw new RuntimeException("Program exceeded max pages: " + limits.getMaximum());
-        var capacity = this.buffer.capacity() + PAGE_SIZE;
+        var capacity = buffer.capacity() + (PAGE_SIZE * size);
         var result = ByteBuffer.allocate(capacity).order(ByteOrder.LITTLE_ENDIAN);
-        var position = this.buffer.position();
-        this.buffer.rewind();
-        result.put(this.buffer);
+        var position = buffer.position();
+        buffer.rewind();
+        result.put(buffer);
         result.position(position);
-        this.buffer = result;
-        this.nPages++;
+        buffer = result;
+        nPages = numPages;
+        return nPages;
     }
 
     public int getInitialSize() {

diff --git a/wasm/scripts/instructions.tsv b/wasm/scripts/instructions.tsv
@@ -41,7 +41,7 @@ i32.store16 <varuint> <varuint> 	$3B
 i64.store8 <varuint> <varuint> 	$3C
 i64.store16 <varuint> <varuint> 	$3D
 i64.store32 <varuint> <varuint> 	$3E
-memory.size 	$3F
+memory.size <varuint> 	$3F
 memory.grow <varuint> 	$40
 i32.const <varsint32> 	$41
 i64.const <varsint64> 	$42

diff --git a/wasm/src/main/java/com/dylibso/chicory/wasm/types/OpCode.java b/wasm/src/main/java/com/dylibso/chicory/wasm/types/OpCode.java
@@ -50,7 +50,7 @@ public enum OpCode {
     I64_STORE8(0x3C), // i64.store8 <varuint> <varuint>
     I64_STORE16(0x3D), // i64.store16 <varuint> <varuint>
     I64_STORE32(0x3E), // i64.store32 <varuint> <varuint>
-    MEMORY_SIZE(0x3F), // memory.size
+    MEMORY_SIZE(0x3F), // memory.size <varuint>
     MEMORY_GROW(0x40), // memory.grow <varuint>
     I32_CONST(0x41), // i32.const <varsint32>
     I64_CONST(0x42), // i64.const <varsint64>
@@ -262,7 +262,7 @@ public static WasmEncoding[] getSignature(OpCode o) {
         signature.put(I64_STORE8, new WasmEncoding[] {WasmEncoding.VARUINT, WasmEncoding.VARUINT});
         signature.put(I64_STORE16, new WasmEncoding[] {WasmEncoding.VARUINT, WasmEncoding.VARUINT});
         signature.put(I64_STORE32, new WasmEncoding[] {WasmEncoding.VARUINT, WasmEncoding.VARUINT});
-        signature.put(MEMORY_SIZE, new WasmEncoding[] {});
+        signature.put(MEMORY_SIZE, new WasmEncoding[] {WasmEncoding.VARUINT});
         signature.put(MEMORY_GROW, new WasmEncoding[] {WasmEncoding.VARUINT});
         signature.put(I32_CONST, new WasmEncoding[] {WasmEncoding.VARSINT32});
         signature.put(I64_CONST, new WasmEncoding[] {WasmEncoding.VARSINT64});