ReturnFloat peephole optimization (#2049)

Co-authored-by: ike709 <[email protected]>
OpenDreamProject · Oct 22, 2024 · 2d93944 · 2d93944
1 parent e8f095f
commit 2d93944
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Showing 5 changed files with 28 additions and 1 deletion.
diff --git a/DMCompiler/Bytecode/DreamProcOpcode.cs b/DMCompiler/Bytecode/DreamProcOpcode.cs
@@ -291,6 +291,8 @@ public enum DreamProcOpcode : byte {
     NullRef = 0x96,
     [OpcodeMetadata(0, OpcodeArgType.Reference)]
     ReturnReferenceValue = 0x97,
+    [OpcodeMetadata(0, OpcodeArgType.Float)]
+    ReturnFloat = 0x98,
 }
 // ReSharper restore MissingBlankLines
 

diff --git a/DMCompiler/Optimizer/PeepholeOptimizations.cs b/DMCompiler/Optimizer/PeepholeOptimizations.cs
@@ -101,6 +101,24 @@ public void Apply(List<IAnnotatedBytecode> input, int index) {
     }
 }
 
+// PushFloat [float]
+// Return
+// -> ReturnFloat [float]
+internal class ReturnFloat : IPeepholeOptimization {
+    public ReadOnlySpan<DreamProcOpcode> GetOpcodes() {
+        return [
+            DreamProcOpcode.PushFloat,
+            DreamProcOpcode.Return
+        ];
+    }
+
+    public void Apply(List<IAnnotatedBytecode> input, int index) {
+        var firstInstruction = IPeepholeOptimization.GetInstructionAndValue(input[index], out var pushVal);
+        IPeepholeOptimization.ReplaceInstructions(input, index, 2,
+            new AnnotatedBytecodeInstruction(DreamProcOpcode.ReturnFloat, [new AnnotatedBytecodeFloat(pushVal, firstInstruction.Location)]));
+    }
+}
+
 // PushReferenceValue [ref]
 // JumpIfFalse [label]
 // -> JumpIfReferenceFalse [ref] [label]

diff --git a/OpenDreamRuntime/Procs/DMOpcodeHandlers.cs b/OpenDreamRuntime/Procs/DMOpcodeHandlers.cs
@@ -3084,6 +3084,11 @@ public static ProcStatus IsTypeDirect(DMProcState state) {
             return ProcStatus.Continue;
         }
 
+        public static ProcStatus ReturnFloat(DMProcState state) {
+            state.SetReturn(new DreamValue(state.ReadFloat()));
+            return ProcStatus.Returned;
+        }
+
         #endregion
     }
 }
diff --git a/OpenDreamRuntime/Procs/DMProc.cs b/OpenDreamRuntime/Procs/DMProc.cs
@@ -320,7 +320,8 @@ public sealed class DMProcState : ProcState {
             {DreamProcOpcode.CreateListNRefs, DMOpcodeHandlers.CreateListNRefs},
             {DreamProcOpcode.CreateListNResources, DMOpcodeHandlers.CreateListNResources},
             {DreamProcOpcode.IsTypeDirect, DMOpcodeHandlers.IsTypeDirect},
-            {DreamProcOpcode.ReturnReferenceValue, DMOpcodeHandlers.ReturnReferenceValue}
+            {DreamProcOpcode.ReturnReferenceValue, DMOpcodeHandlers.ReturnReferenceValue},
+            {DreamProcOpcode.ReturnFloat, DMOpcodeHandlers.ReturnFloat}
         };
 
         public static readonly unsafe delegate*<DMProcState, ProcStatus>[] OpcodeHandlers;

diff --git a/OpenDreamRuntime/Procs/ProcDecoder.cs b/OpenDreamRuntime/Procs/ProcDecoder.cs
@@ -83,6 +83,7 @@ public ITuple DecodeInstruction() {
                 return (opcode, ReadValueType());
 
             case DreamProcOpcode.PushFloat:
+            case DreamProcOpcode.ReturnFloat:
                 return (opcode, ReadFloat());
 
             case DreamProcOpcode.SwitchOnFloat: