From eefe782dd6ea23e2bb762ac6e9ea2f783d34c154 Mon Sep 17 00:00:00 2001
From: Christoffer Lerno <christoffer@aegik.com>
Date: Mon, 20 Dec 2021 21:35:36 +0100
Subject: [PATCH] Fix constant evaluation of | & ^ >> <<

---
 src/compiler/sema_expr.c                       |  6 ++++--
 .../compile_time/compile_time_bitops.c3t       | 18 ++++++++++++++++++
 2 files changed, 22 insertions(+), 2 deletions(-)
 create mode 100644 test/test_suite/compile_time/compile_time_bitops.c3t

diff --git a/src/compiler/sema_expr.c b/src/compiler/sema_expr.c
index b2d279304..a50da2421 100644
--- a/src/compiler/sema_expr.c
+++ b/src/compiler/sema_expr.c
@@ -4792,8 +4792,9 @@ static bool sema_expr_analyse_bit(Context *context, Expr *expr, Expr *left, Expr
 	// 3. Do constant folding if both sides are constant.
 	if (expr_both_const(left, right))
 	{
+		BinaryOp op = expr->binary_expr.operator;
 		expr_replace(expr, left);
-		switch (expr->binary_expr.operator)
+		switch (op)
 		{
 			case BINARYOP_BIT_AND:
 				expr->const_expr.ixx = int_and(left->const_expr.ixx, right->const_expr.ixx);
@@ -4857,8 +4858,9 @@ static bool sema_expr_analyse_shift(Context *context, Expr *expr, Expr *left, Ex
 		// 5. Fold constant expressions.
 		if (IS_CONST(left))
 		{
+			bool shr = expr->binary_expr.operator == BINARYOP_SHR;
 			expr_replace(expr, left);
-			if (expr->binary_expr.operator == BINARYOP_SHR)
+			if (shr)
 			{
 				expr->const_expr.ixx = int_shr64(left->const_expr.ixx, right->const_expr.ixx.i.low);
 			}
diff --git a/test/test_suite/compile_time/compile_time_bitops.c3t b/test/test_suite/compile_time/compile_time_bitops.c3t
new file mode 100644
index 000000000..eb3cb79be
--- /dev/null
+++ b/test/test_suite/compile_time/compile_time_bitops.c3t
@@ -0,0 +1,18 @@
+// #target: x64-darwin
+module foo;
+
+int x1 = 2 ^ 4;
+int x2 = 2 | 4;
+int x3 = 2 & 4;
+int y1 = 4 << 2;
+int y2 = 4 >> 2;
+int y3 = ~4;
+
+/* #expect: foo.ll
+
+@foo.x1 = global i32 6, align 4
+@foo.x2 = global i32 6, align 4
+@foo.x3 = global i32 0, align 4
+@foo.y1 = global i32 16, align 4
+@foo.y2 = global i32 1, align 4
+@foo.y3 = global i32 -5, align 4
\ No newline at end of file