Add support for using enums in case statement

ForNeVeR · Sep 2, 2024 · c13819f · c13819f
1 parent 18d6d82
commit c13819f
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Showing 4 changed files with 34 additions and 2 deletions.
diff --git a/Cesium.CodeGen.Tests/CodeGenEnumTests.cs b/Cesium.CodeGen.Tests/CodeGenEnumTests.cs
@@ -60,4 +60,17 @@ void test()
 {
     work(Green);
 }");
+
+    [Fact]
+    public Task EnumInCase() => DoTest(@"
+enum Colour { Red, Green, Blue };
+
+void test()
+{
+    enum Colour x = 42;
+    switch (x) {
+        case Blue:
+            break;
+    }
+}");
 }
diff --git a/Cesium.CodeGen.Tests/CodeGenSwitchTests.cs b/Cesium.CodeGen.Tests/CodeGenSwitchTests.cs
@@ -44,7 +44,7 @@ public void NonConstEval() => DoesNotCompile(@"int main()
     int x = 0;
     switch(x) { case 1 + x: break; };
     return 1;
-}", "Expression Cesium.CodeGen.Ir.Expressions.IdentifierExpression cannot be evaluated as constant expression.");
+}", "Expression Cesium.CodeGen.Ir.Expressions.GetValueExpression cannot be evaluated as constant expression.");
 
     [Fact]
     public Task MultiCases() => DoTest(@"int main()

diff --git a/Cesium.CodeGen.Tests/verified/CodeGenEnumTests.EnumInCase.verified.txt b/Cesium.CodeGen.Tests/verified/CodeGenEnumTests.EnumInCase.verified.txt
@@ -0,0 +1,19 @@
+System.Void <Module>::test()
+  Locals:
+    System.Int32 V_0
+    System.Int32 V_1
+  IL_0000: ldc.i4.s 42
+  IL_0002: stloc.0
+  IL_0003: ldloc.0
+  IL_0004: stloc.1
+  IL_0005: ldloc.1
+  IL_0006: ldc.i4.2
+  IL_0007: ceq
+  IL_0009: brfalse IL_0013
+  IL_000e: br IL_0019
+  IL_0013: nop
+  IL_0014: br IL_001f
+  IL_0019: nop
+  IL_001a: br IL_001f
+  IL_001f: nop
+  IL_0020: ret
diff --git a/Cesium.CodeGen/Ir/Lowering/BlockItemLowering.cs b/Cesium.CodeGen/Ir/Lowering/BlockItemLowering.cs
@@ -193,7 +193,7 @@ void ProcessCaseStatement(CaseStatement caseStatement, BlockScope switchBlock, s
                         {
                             if (caseStatement.Expression != null)
                             {
-                                var constValue = ConstantEvaluator.GetConstantValue(caseStatement.Expression);
+                                var constValue = ConstantEvaluator.GetConstantValue(caseStatement.Expression.Lower(switchBlock));
                                 switchBlock.SwitchCases.Add(new SwitchCase(new ConstantLiteralExpression(constValue), label));
                             }
                             else