Add option to show instruction opcodes

Author: tathanhdinh

src/fasmi/Disassembly.fs

@@ -76,7 +76,7 @@ let formatterOptions = FormatterOptions(
 
 
 // disassemble a single method
-let disassembleConcreteMethod (runtime: ClrRuntime) (mthinfo: MethodBase) platform (writer: TextWriter) =
+let disassembleConcreteMethod (runtime: ClrRuntime) (mthinfo: MethodBase) platform showOpcodes (writer: TextWriter) =
 
     runtime.FlushCachedData()
     let h = mthinfo.MethodHandle
@@ -139,7 +139,13 @@ let disassembleConcreteMethod (runtime: ClrRuntime) (mthinfo: MethodBase) platfo
                 // render instructions
                 for inst in decoder do
                     formatter.Format(&inst, out)
-                    writer.WriteLine $"L%04x{inst.IP - address}: %s{out.ToStringAndReset()}"
+                    let inst_relative_ip = int <| inst.IP - address
+                    if showOpcodes then
+                        let inst_opcode_hex = bytes[inst_relative_ip..inst_relative_ip + inst.Length - 1]
+                                                |> Array.fold (fun hex b -> sprintf "%s %02x" hex b) ""
+                        writer.WriteLine $"L%04x{inst_relative_ip}: %45s{inst_opcode_hex}  %s{out.ToStringAndReset()}"
+                    else
+                        writer.WriteLine $"L%04x{inst_relative_ip}: %s{out.ToStringAndReset()}"
                     writer.Flush()
 
 
@@ -153,9 +159,9 @@ let outputGenericMethod (runtime: ClrRuntime) (mthinfo: MethodBase) (writer: Tex
     writer.WriteLine $"; generic method cannot be jitted. provide explicit types"
     writer.Flush()
 
-let disassembleMethod runtime (mthinfo: MethodBase) platform writer =
+let disassembleMethod runtime (mthinfo: MethodBase) platform showOpcodes writer =
     if not mthinfo.IsGenericMethodDefinition && not mthinfo.DeclaringType.IsGenericTypeDefinition then
-        disassembleConcreteMethod runtime mthinfo platform writer
+        disassembleConcreteMethod runtime mthinfo platform showOpcodes writer
     else
         outputGenericMethod runtime mthinfo writer
 
@@ -167,7 +173,7 @@ let withRuntime f =
 
 
 // disassemble assembly as jitted x86/x64 to text writer
-let disassemble asmPath (writer: TextWriter) platform =
+let disassemble asmPath (writer: TextWriter) platform showOpcodes =
 
     // attach to self
     withRuntime (fun runtime ->
@@ -188,13 +194,13 @@ let disassemble asmPath (writer: TextWriter) platform =
 
             for mth in getAllMethods ty do
                 if mth.DeclaringType <> typeof<obj> then
-                    disassembleMethod runtime mth platform writer
+                    disassembleMethod runtime mth platform showOpcodes writer
 
 
             for sty in ty.GetNestedTypes() do
                 for mth in getAllMethods sty do
                     if mth.DeclaringType <> typeof<obj> then
-                        disassembleMethod runtime mth platform writer
+                        disassembleMethod runtime mth platform showOpcodes writer
     )
 
 /// disassemble assembly as IL to text writer
@@ -205,19 +211,19 @@ let ildasm asmPath writer =
     disass.WriteModuleContents(pe)
 
 /// disassemble assembly to writer
-let decompile asmPath writer language platform =
+let decompile asmPath writer language platform showOpcodes =
     match language with
-    | Asm -> disassemble asmPath writer platform
+    | Asm -> disassemble asmPath writer platform showOpcodes
     | IL -> ildasm asmPath writer
 
 /// disassemble assembly to file
-let decompileToFile asmPath outPath language platform =
+let decompileToFile asmPath outPath language platform showOpcodes =
     use w = File.CreateText(outPath)
-    decompile asmPath w language platform
+    decompile asmPath w language platform showOpcodes
 
 
 /// disassemble assembly to console
-let decompileToConsole asmPath language platform  =
+let decompileToConsole asmPath language platform showOpcodes =
     use s = Console.OpenStandardOutput()
     use w = new IO.StreamWriter(s)
-    decompile asmPath w language platform
+    decompile asmPath w language platform showOpcodes

src/fasmi/Program.fs

@@ -9,6 +9,7 @@ type Cmd =
     | [<Mandatory; MainCommand; AltCommandLine("-s")>]Source of string
     | [<AltCommandLine("-c")>] Console
     | [<AltCommandLine("-o")>] Output of string
+    | [<AltCommandLine("-x")>] Hex
     | [<AltCommandLine("-w")>] Watch
     | [<AltCommandLine("-p")>] Platform of Disassembly.Platform
     | [<AltCommandLine("-l")>] Language of Disassembly.Language
@@ -20,6 +21,7 @@ type Cmd =
             | Source _ -> "the source fsx or dotnet assembly file"
             | Console -> "output to console"
             | Output _ -> "specifiy the output file" 
+            | Hex _ -> "show instruction opcodes"
             | Watch -> "run in watch mode"
             | Platform _ -> "specify the platform for disassembly"
             | Language _ -> "specify the output language (asm/il)"
@@ -146,13 +148,14 @@ let main argv =
 
 
             logf "Disassembly"
-            
+
+            let showOpcodes = cmd.Contains Hex
 
             // disassemble
             if cmd.Contains Console then
-                Disassembly.decompileToConsole asmPath language platform
+                Disassembly.decompileToConsole asmPath language platform showOpcodes
             else
-                Disassembly.decompileToFile asmPath out language platform
+                Disassembly.decompileToFile asmPath out language platform showOpcodes
 
         if cmd.Contains Watch then
             // run in watch mode

tests/fasmi.tests/Tests.fs

@@ -32,7 +32,7 @@ let disassembleFromSourceProject methodName =
 
     Disassembly.withRuntime (fun runtime ->
         use writer = new IO.StringWriter()
-        Disassembly.disassembleMethod runtime mth Disassembly.Platform.X64 writer
+        Disassembly.disassembleMethod runtime mth Disassembly.Platform.X64 false writer
         writer.Flush()
         writer.ToString())