From 12051e75440f65bc4cabf88ca2178085c38c4f87 Mon Sep 17 00:00:00 2001
From: Christian Buttner <christian@cbuttner.de>
Date: Thu, 4 Jul 2024 00:44:32 +0200
Subject: [PATCH] Fix `$$unaligned_store` arg check and add test. (#1224)

Fix `$$unaligned_store` arg check and add test.
---
 lib/std/core/mem.c3                           | 16 +++++---
 src/compiler/sema_builtins.c                  |  3 +-
 .../builtins/unaligned_load_store.c3t         | 40 +++++++++++++++++++
 3 files changed, 52 insertions(+), 7 deletions(-)
 create mode 100644 test/test_suite/builtins/unaligned_load_store.c3t

diff --git a/lib/std/core/mem.c3 b/lib/std/core/mem.c3
index c604c8125..11ebb887f 100644
--- a/lib/std/core/mem.c3
+++ b/lib/std/core/mem.c3
@@ -162,9 +162,9 @@ macro @scatter_aligned(ptrvec, value, bool[<*>] mask, usz $alignment)
 }
 
 /**
- * @param [in] x "the variable or dereferenced pointer to load."
- * @param $alignment "the alignment to assume for the load"
- * @return "returns the value of x"
+ * @param [in] x "The variable or dereferenced pointer to load."
+ * @param $alignment "The alignment to assume for the load"
+ * @return "The value of x"
  *
  * @require @constant_is_power_of_2($alignment) : "The alignment must be a power of two"
  **/
@@ -174,13 +174,17 @@ macro @unaligned_load(&x, usz $alignment) @builtin
 }
 
 /**
- * @require $assignable(y, $typeof(*x)) : "The value doesn't match the variable"
+ * @param [out] x "The variable or dereferenced pointer to store to."
+ * @param value "The value to store."
+ * @param $alignment "The alignment to assume for the store"
+ * @return "The value of x"
  *
+ * @require $assignable(value, $typeof(*x)) : "The value doesn't match the variable"
  * @require @constant_is_power_of_2($alignment) : "The alignment must be a power of two"
  **/
-macro @unaligned_store(&x, y, usz $alignment) @builtin
+macro @unaligned_store(&x, value, usz $alignment) @builtin
 {
-	return $$unaligned_store(x, ($typeof(*x))y, $alignment);
+	return $$unaligned_store(x, ($typeof(*x))value, $alignment);
 }
 
 macro @volatile_load(&x) @builtin
diff --git a/src/compiler/sema_builtins.c b/src/compiler/sema_builtins.c
index 93a9d162b..e5395306e 100644
--- a/src/compiler/sema_builtins.c
+++ b/src/compiler/sema_builtins.c
@@ -838,7 +838,8 @@ bool sema_expr_analyse_builtin_call(SemaContext *context, Expr *expr)
 		case BUILTIN_UNALIGNED_STORE:
 		{
 			assert(arg_count == 3);
-			if (!sema_check_builtin_args(context, args, (BuiltinArg[]) {BA_POINTER, BA_INTEGER }, 2)) return false;
+			if (!sema_check_builtin_args(context, args, (BuiltinArg[]) {BA_POINTER}, 1)) return false;
+			if (!sema_check_builtin_args(context, &args[2], (BuiltinArg[]) {BA_INTEGER}, 1)) return false;
 			Type *original = type_flatten(args[0]->type);
 			if (!sema_check_alignment_expression(context, args[2])) return false;
 			if (original != type_voidptr)
diff --git a/test/test_suite/builtins/unaligned_load_store.c3t b/test/test_suite/builtins/unaligned_load_store.c3t
new file mode 100644
index 000000000..58b3d10c4
--- /dev/null
+++ b/test/test_suite/builtins/unaligned_load_store.c3t
@@ -0,0 +1,40 @@
+module test;
+
+struct Foo
+{
+  float[4] a;
+}
+
+fn void main()
+{
+  Foo* foo;
+  float[<4>] a @align(1) @noinit;
+
+  a = *(float[<4>]*)&foo.a;
+  *(float[<4>]*)&foo.a = a;
+
+  a = $$unaligned_load((float[<4>]*)&foo.a, 1);
+  $$unaligned_store((float[<4>]*)&foo.a, a, 1);
+}
+
+/* #expect: test.ll
+
+define void @test.main() #0 {
+entry:
+  %foo = alloca ptr, align 8
+  %a = alloca <4 x float>, align 1
+  store ptr null, ptr %foo, align 8
+  %0 = load ptr, ptr %foo, align 8
+  %1 = load <4 x float>, ptr %0, align 16
+  store <4 x float> %1, ptr %a, align 1
+  %2 = load ptr, ptr %foo, align 8
+  %3 = load <4 x float>, ptr %a, align 1
+  store <4 x float> %3, ptr %2, align 16
+  %4 = load ptr, ptr %foo, align 8
+  %5 = load <4 x float>, ptr %4, align 1
+  store <4 x float> %5, ptr %a, align 1
+  %6 = load ptr, ptr %foo, align 8
+  %7 = load <4 x float>, ptr %a, align 1
+  store <4 x float> %7, ptr %6, align 1
+  ret void
+}