From 64a4665dfd998d674e18b9d221d89793b7d209e7 Mon Sep 17 00:00:00 2001
From: Edgar Luque <git@edgarluque.com>
Date: Fri, 16 Feb 2024 11:09:49 +0100
Subject: [PATCH] fix: fix a miscompilation

---
 lib/edlang_codegen_llvm/src/codegen.rs        |  2 +-
 lib/edlang_driver/tests/programs.rs           | 73 ++++++++++++++++++-
 lib/edlang_driver/tests/programs/factorial.ed |  4 +-
 lib/edlang_lowering/src/lib.rs                |  1 +
 programs/factorial.ed                         |  2 +-
 5 files changed, 77 insertions(+), 5 deletions(-)

diff --git a/lib/edlang_codegen_llvm/src/codegen.rs b/lib/edlang_codegen_llvm/src/codegen.rs
index 978bc018b..b2b9f69a9 100644
--- a/lib/edlang_codegen_llvm/src/codegen.rs
+++ b/lib/edlang_codegen_llvm/src/codegen.rs
@@ -570,7 +570,7 @@ fn compile_bin_op<'ctx>(
                     .as_basic_value_enum()
             } else {
                 ctx.builder
-                    .build_int_add(lhs_value.into_int_value(), rhs_value.into_int_value(), "")?
+                    .build_int_mul(lhs_value.into_int_value(), rhs_value.into_int_value(), "")?
                     .as_basic_value_enum()
             };
             (value, lhs_ty)
diff --git a/lib/edlang_driver/tests/programs.rs b/lib/edlang_driver/tests/programs.rs
index 9c88ce2fc..75080be9e 100644
--- a/lib/edlang_driver/tests/programs.rs
+++ b/lib/edlang_driver/tests/programs.rs
@@ -7,7 +7,16 @@ mod common;
 #[test_case(include_str!("programs/simple.ed"), "simple", false, 1, &["a", "b"] ; "simple.ed 3")]
 #[test_case(include_str!("programs/basic_ifs.ed"), "basic_ifs", false, 9, &[] ; "basic_ifs")]
 #[test_case(include_str!("programs/while.ed"), "while", false, 10, &[] ; "r#while")]
-#[test_case(include_str!("programs/factorial.ed"), "factorial", false, 6, &[] ; "factorial")]
+#[test_case(include_str!("programs/factorial.ed"), "factorial", false, 24, &[] ; "factorial")]
+#[test_case(TEST_ADD, "TEST_ADD", false, 2, &[] ; "TEST_ADD")]
+#[test_case(TEST_SUB, "TEST_SUB", false, 1, &[] ; "TEST_SUB")]
+#[test_case(TEST_MUL, "TEST_MUL", false, 4, &[] ; "TEST_MUL")]
+#[test_case(TEST_DIV, "TEST_DIV", false, 2, &[] ; "TEST_DIV")]
+#[test_case(TEST_REM, "TEST_REM", false, 0, &[] ; "TEST_REM")]
+#[test_case(TEST_IF_BOTH, "TEST_IF_BOTH", false, 1, &[] ; "TEST_IF_BOTH")]
+#[test_case(TEST_IF_BOTH, "TEST_IF_BOTH", false, 2, &["a"] ; "TEST_IF_BOTH args")]
+#[test_case(TEST_IF_NO_ELSE, "TEST_IF_NO_ELSE", false, 1, &[] ; "TEST_IF_NO_ELSE")]
+#[test_case(TEST_IF_NO_ELSE, "TEST_IF_NO_ELSE", false, 2, &["a"] ; "TEST_IF_NO_ELSE args")]
 fn example_tests(source: &str, name: &str, is_library: bool, status_code: i32, args: &[&str]) {
     let program = compile_program(source, name, is_library).unwrap();
 
@@ -21,3 +30,65 @@ fn example_tests(source: &str, name: &str, is_library: bool, status_code: i32, a
         name
     );
 }
+
+const TEST_ADD: &str = r#"
+mod Main {
+    pub fn main() -> i32 {
+        let b: i32 = 1 + 1;
+        return b;
+    }
+}
+"#;
+const TEST_SUB: &str = r#"
+mod Main {
+    pub fn main() -> i32 {
+        let b: i32 = 2 - 1;
+        return b;
+    }
+}
+"#;
+const TEST_MUL: &str = r#"
+mod Main {
+    pub fn main() -> i32 {
+        let b: i32 = 2 * 2;
+        return b;
+    }
+}
+"#;
+const TEST_DIV: &str = r#"
+mod Main {
+    pub fn main() -> i32 {
+        let b: i32 = 4 / 2;
+        return b;
+    }
+}
+"#;
+const TEST_REM: &str = r#"
+mod Main {
+    pub fn main() -> i32 {
+        let b: i32 = 4 % 2;
+        return b;
+    }
+}
+"#;
+const TEST_IF_BOTH: &str = r#"
+mod Main {
+    pub fn main(argc: i32) -> i32 {
+        if argc == 1 {
+            return 1;
+        } else {
+            return 2;
+        }
+    }
+}
+"#;
+const TEST_IF_NO_ELSE: &str = r#"
+mod Main {
+    pub fn main(argc: i32) -> i32 {
+        if argc == 1 {
+            return 1;
+        }
+        return 2;
+    }
+}
+"#;
diff --git a/lib/edlang_driver/tests/programs/factorial.ed b/lib/edlang_driver/tests/programs/factorial.ed
index 60f6d6fad..28a8e6772 100644
--- a/lib/edlang_driver/tests/programs/factorial.ed
+++ b/lib/edlang_driver/tests/programs/factorial.ed
@@ -1,11 +1,11 @@
 mod Main {
     pub fn main() -> i32 {
-        let b: i32 = factorial(3);
+        let b: i32 = factorial(4);
         return b;
     }
 
     fn factorial(n: i32) -> i32 {
-        if n == 1 {
+        if n == 0 {
             return n;
         } else {
             return n * factorial(n - 1);
diff --git a/lib/edlang_lowering/src/lib.rs b/lib/edlang_lowering/src/lib.rs
index 426d0195a..1d3be6ba3 100644
--- a/lib/edlang_lowering/src/lib.rs
+++ b/lib/edlang_lowering/src/lib.rs
@@ -459,6 +459,7 @@ fn lower_binary_expr(
 ) -> (ir::RValue, TypeKind) {
     trace!("lowering binary op: {:?}", op);
 
+    // todo: if lhs or rhs is a simple place, dont make another temporary?
     let (lhs, lhs_ty) = if type_hint.is_none() {
         let ty = find_expr_type(builder, lhs)
             .unwrap_or_else(|| find_expr_type(builder, rhs).expect("cant find type"));
diff --git a/programs/factorial.ed b/programs/factorial.ed
index c7d717845..7123369fb 100644
--- a/programs/factorial.ed
+++ b/programs/factorial.ed
@@ -1,6 +1,6 @@
 mod Main {
     pub fn main() -> i32 {
-        let b: i32 = factorial(2);
+        let b: i32 = factorial(4);
         return b;
     }