optimize HandleMathClamp

neo-project · Sep 5, 2024 · 7c226a0 · 7c226a0
1 parent 6039fc5
commit 7c226a0
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Showing 3 changed files with 27 additions and 35 deletions.
diff --git a/src/Neo.Compiler.CSharp/MethodConvert/System/SystemCall.Math.cs b/src/Neo.Compiler.CSharp/MethodConvert/System/SystemCall.Math.cs
@@ -306,41 +306,33 @@ private static void HandleMathClamp(MethodConvert methodConvert, SemanticModel m
         if (arguments is not null)
             methodConvert.PrepareArgumentsForMethod(model, symbol, arguments, CallingConvention.StdCall);
 
-        var endTarget = new JumpTarget();
         var exceptionTarget = new JumpTarget();
         var minTarget = new JumpTarget();
         var maxTarget = new JumpTarget();
-        methodConvert.AddInstruction(OpCode.DUP);// 5 0 10 10
-        methodConvert.AddInstruction(OpCode.ROT);// 5 10 10 0
-        methodConvert.AddInstruction(OpCode.DUP);// 5 10 10 0 0
-        methodConvert.AddInstruction(OpCode.ROT);// 5 10 0 0 10
-        methodConvert.Jump(OpCode.JMPLT, exceptionTarget);// 5 10 0
-        methodConvert.AddInstruction(OpCode.THROW);
+        // Evaluation stack: value=5 min=0 max=10 <- top
+        methodConvert.AddInstruction(OpCode.OVER);  // 5 0 10 0
+        methodConvert.AddInstruction(OpCode.OVER);  // 5 0 10 0 10 <- top
+        methodConvert.Jump(OpCode.JMPLE, exceptionTarget);  // 5 0 10  // if 0 <= 10, continue execution
+        methodConvert.Push("min>max");
+        methodConvert.AddInstruction(OpCode.ABORTMSG);
         exceptionTarget.Instruction = methodConvert.AddInstruction(OpCode.NOP);
-        methodConvert.AddInstruction(OpCode.ROT);// 10 0 5
-        methodConvert.AddInstruction(OpCode.DUP);// 10 0 5 5
-        methodConvert.AddInstruction(OpCode.ROT);// 10 5 5 0
-        methodConvert.AddInstruction(OpCode.DUP);// 10 5 5 0 0
-        methodConvert.AddInstruction(OpCode.ROT);// 10 5 0 0 5
-        methodConvert.Jump(OpCode.JMPGT, minTarget);// 10 5 0
-        methodConvert.AddInstruction(OpCode.DROP);// 10 5
-        methodConvert.AddInstruction(OpCode.DUP);// 10 5 5
-        methodConvert.AddInstruction(OpCode.ROT);// 5 5 10
-        methodConvert.AddInstruction(OpCode.DUP);// 5 5 10 10
-        methodConvert.AddInstruction(OpCode.ROT);// 5 10 10 5
-        methodConvert.Jump(OpCode.JMPLT, maxTarget);// 5 10
-        methodConvert.AddInstruction(OpCode.DROP);
-        methodConvert.Jump(OpCode.JMP, endTarget);
-        minTarget.Instruction = methodConvert.AddInstruction(OpCode.NOP);
-        methodConvert.AddInstruction(OpCode.REVERSE3);
-        methodConvert.AddInstruction(OpCode.DROP);
-        methodConvert.AddInstruction(OpCode.DROP);
-        methodConvert.Jump(OpCode.JMP, endTarget);
-        maxTarget.Instruction = methodConvert.AddInstruction(OpCode.NOP);
-        methodConvert.AddInstruction(OpCode.SWAP);
-        methodConvert.AddInstruction(OpCode.DROP);
-        methodConvert.Jump(OpCode.JMP, endTarget);
-        endTarget.Instruction = methodConvert.AddInstruction(OpCode.NOP);
+        methodConvert.AddInstruction(OpCode.REVERSE3);  // 10 0 5
+        methodConvert.AddInstruction(OpCode.OVER);  // 10 0 5 0
+        methodConvert.AddInstruction(OpCode.OVER);  // 10 0 5 0 5
+        methodConvert.Jump(OpCode.JMPGE, minTarget);  // 10 0 5; should return 0 if JMPed
+        methodConvert.AddInstruction(OpCode.NIP);  // 10 5
+        methodConvert.AddInstruction(OpCode.OVER);  // 10 5 10
+        methodConvert.AddInstruction(OpCode.OVER);  // 10 5 10 5
+        methodConvert.Jump(OpCode.JMPLE, maxTarget);  // 10 5; should return 10 if JMPed
+        methodConvert.AddInstruction(OpCode.NIP);  // 5; should return 5
+        methodConvert.AddInstruction(OpCode.RET);
+        minTarget.Instruction = methodConvert.AddInstruction(OpCode.NOP);  // 10 0 5; should return 0
+        methodConvert.AddInstruction(OpCode.DROP);  // 10 0; should return 0
+        methodConvert.AddInstruction(OpCode.NIP);  // 0; should return 0
+        methodConvert.AddInstruction(OpCode.RET);
+        maxTarget.Instruction = methodConvert.AddInstruction(OpCode.NOP);  // 10 5; should return 10
+        methodConvert.AddInstruction(OpCode.DROP);  // 10; should return 10
+        methodConvert.AddInstruction(OpCode.RET);
     }
 
     private static void HandleMathBigMul(MethodConvert methodConvert, SemanticModel model, IMethodSymbol symbol, ExpressionSyntax? instanceExpression, IReadOnlyList<SyntaxNode>? arguments)