From b830e9c4971023982d6a86b85d5322931968538e Mon Sep 17 00:00:00 2001
From: Kelvin Nishikawa <kelnishi@gmail.com>
Date: Mon, 18 Nov 2024 23:21:01 -0800
Subject: [PATCH] Removing conditional multi-memory support, but making
 Spec.Test fail multiple memory validation.

---
 Spec.Test/WastTests.cs               |  4 ++++
 Wacs.Core/Instructions/MemoryBulk.cs | 28 +---------------------------
 Wacs.Core/Types/MemArg.cs            |  4 ++--
 Wacs.Core/Validation/Validation.cs   | 13 ++++++++-----
 Wacs.Core/Wacs.Core.csproj           |  4 ++--
 5 files changed, 17 insertions(+), 36 deletions(-)

diff --git a/Spec.Test/WastTests.cs b/Spec.Test/WastTests.cs
index 78b594d..f3af9f5 100644
--- a/Spec.Test/WastTests.cs
+++ b/Spec.Test/WastTests.cs
@@ -16,6 +16,7 @@
 
 using Wacs.Core;
 using Wacs.Core.Runtime;
+using Wacs.Core.Validation;
 using Xunit;
 using Xunit.Abstractions;
 
@@ -38,6 +39,9 @@ public void RunWast(WastJson.WastJson file)
             SpecTestEnv env = new SpecTestEnv();
             WasmRuntime runtime = new();
             env.BindToRuntime(runtime);
+
+            //Make multiple memories fail validation
+            ModuleValidator.ValidateMultipleMemories = false;
             
             Module? module = null;
             foreach (var command in file.Commands)
diff --git a/Wacs.Core/Instructions/MemoryBulk.cs b/Wacs.Core/Instructions/MemoryBulk.cs
index 438bd2f..386cae1 100644
--- a/Wacs.Core/Instructions/MemoryBulk.cs
+++ b/Wacs.Core/Instructions/MemoryBulk.cs
@@ -64,11 +64,6 @@ public override void Execute(ExecContext context)
         public override IInstruction Parse(BinaryReader reader)
         {
             M = (MemIdx)reader.ReadByte();
-#if !MULTI_MEMORY
-            if (M != 0x00)
-                throw new FormatException(
-                    $"Invalid memory.size. Multiple memories are not yet supported. memidx:{M}");
-#endif
             return this;
         }
     }
@@ -126,11 +121,6 @@ public override void Execute(ExecContext context)
         public override IInstruction Parse(BinaryReader reader)
         {
             M = (MemIdx)reader.ReadByte();
-#if !MULTI_MEMORY
-            if (M != 0x00)
-                throw new FormatException(
-                    $"Invalid memory.grow. Multiple memories are not yet supported. memidx:{M}");
-#endif
             return this;
         }
     }
@@ -239,12 +229,7 @@ public override IInstruction Parse(BinaryReader reader)
         {
             X = (DataIdx)reader.ReadLeb128_u32();
             Y = (MemIdx)reader.ReadByte();
-
-#if !MULTI_MEMORY
-            if (Y != 0x00)
-                throw new FormatException(
-                    $"Invalid memory.init. Multiple memories are not yet supported. memidx:{Y}");
-#endif
+            
             return this;
         }
 
@@ -422,13 +407,6 @@ public override IInstruction Parse(BinaryReader reader)
         {
             SrcX = (MemIdx)reader.ReadByte();
             DstY = (MemIdx)reader.ReadByte();
-#if !MULTI_MEMORY
-            if (SrcX != 0x00 || DstY != 0x00)
-            {
-                throw new FormatException(
-                    $"Invalid memory.copy. Multiple memories are not yet supported. {SrcX} -> {DstY}");
-            }
-#endif
             return this;
         }
     }
@@ -513,10 +491,6 @@ public override void Execute(ExecContext context)
         public override IInstruction Parse(BinaryReader reader)
         {
             X = (MemIdx)reader.ReadByte();
-#if !MULTI_MEMORY
-            if (X.Value != 0x00)
-                throw new FormatException($"Invalid memory.fill. Multiple memories are not yet supported. {X}");
-#endif
             return this;
         }
     }
diff --git a/Wacs.Core/Types/MemArg.cs b/Wacs.Core/Types/MemArg.cs
index 4e05c56..3d8e880 100644
--- a/Wacs.Core/Types/MemArg.cs
+++ b/Wacs.Core/Types/MemArg.cs
@@ -43,12 +43,12 @@ public static MemArg Parse(BinaryReader reader)
                 throw new InvalidDataException($"Memory alignment exceeds page size");
 
             MemIdx idx = default;
-#if MULTI_MEMORY
+
             if (align.HasFlag(Alignment.MemIdxSet))
             {
                 idx = (MemIdx)reader.ReadLeb128_s32();
             }
-#endif
+
             uint offset = reader.ReadLeb128_u32();
             return new MemArg(align, offset, idx);
         }
diff --git a/Wacs.Core/Validation/Validation.cs b/Wacs.Core/Validation/Validation.cs
index 64b4b4c..0f70b49 100644
--- a/Wacs.Core/Validation/Validation.cs
+++ b/Wacs.Core/Validation/Validation.cs
@@ -24,6 +24,8 @@ namespace Wacs.Core.Validation
     /// </summary>
     public class ModuleValidator : AbstractValidator<Module>
     {
+        public static bool ValidateMultipleMemories = true;
+
         public ModuleValidator()
         {
             //Set the validation context
@@ -39,11 +41,12 @@ public ModuleValidator()
                 .SetValidator(new Module.Function.Validator()).OverridePropertyName("Function");
             RuleForEach(module => module.Tables).SetValidator(new TableType.Validator());
             RuleForEach(module => module.Memories).SetValidator(new MemoryType.Validator());
-#if !MULTI_MEMORY
-            RuleFor(module => module.MemoryCount)
-                .LessThan(2)
-                .WithMessage("Multiple memories are not supported.");
-#endif
+            if (!ValidateMultipleMemories)
+            {
+                RuleFor(module => module.MemoryCount)
+                    .LessThan(2)
+                    .WithMessage("Multiple memories are not supported.");
+            }
             RuleForEach(module => module.Globals).SetValidator(new Module.Global.Validator());
             RuleForEach(module => module.Exports).SetValidator(new Module.Export.Validator());
             RuleForEach(module => module.Elements).SetValidator(new Module.ElementSegment.Validator());
diff --git a/Wacs.Core/Wacs.Core.csproj b/Wacs.Core/Wacs.Core.csproj
index 9c10c32..d3cb041 100644
--- a/Wacs.Core/Wacs.Core.csproj
+++ b/Wacs.Core/Wacs.Core.csproj
@@ -36,12 +36,12 @@
   </ItemGroup>
   
   <PropertyGroup Condition=" '$(Configuration)' == 'Debug' ">
-    <DefineConstants>TRACE;MULTI_MEMORY</DefineConstants>
+    <DefineConstants>TRACE;</DefineConstants>
   </PropertyGroup>
 
   <PropertyGroup Condition=" '$(Configuration)' == 'Release' ">
     <DebugSymbols>true</DebugSymbols>
-    <DefineConstants>TRACE;MULTI_MEMORY</DefineConstants>
+    <DefineConstants>TRACE;</DefineConstants>
   </PropertyGroup>