From 40a2dfc12a611082ba6810c566a6a46acdb864fc Mon Sep 17 00:00:00 2001
From: Veikka Tuominen <git@vexu.eu>
Date: Wed, 9 Nov 2022 18:32:15 +0200
Subject: [PATCH] Sema: coerce array operands to shuffle

Closes #13494
---
 src/Sema.zig             |  4 ++--
 test/behavior/vector.zig | 15 +++++++++++++++
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/src/Sema.zig b/src/Sema.zig
index b93a892dcc..51b1592c26 100644
--- a/src/Sema.zig
+++ b/src/Sema.zig
@@ -20179,8 +20179,8 @@ fn analyzeShuffle(
         .elem_type = elem_ty,
     });
 
-    if (maybe_a_len == null) a = try sema.addConstUndef(a_ty);
-    if (maybe_b_len == null) b = try sema.addConstUndef(b_ty);
+    if (maybe_a_len == null) a = try sema.addConstUndef(a_ty) else a = try sema.coerce(block, a_ty, a, a_src);
+    if (maybe_b_len == null) b = try sema.addConstUndef(b_ty) else b = try sema.coerce(block, b_ty, b, b_src);
 
     const operand_info = [2]std.meta.Tuple(&.{ u64, LazySrcLoc, Type }){
         .{ a_len, a_src, a_ty },
diff --git a/test/behavior/vector.zig b/test/behavior/vector.zig
index 1f4faae636..36a51d8275 100644
--- a/test/behavior/vector.zig
+++ b/test/behavior/vector.zig
@@ -3,6 +3,7 @@ const builtin = @import("builtin");
 const mem = std.mem;
 const math = std.math;
 const expect = std.testing.expect;
+const expectEqual = std.testing.expectEqual;
 
 test "implicit cast vector to array - bool" {
     if (builtin.zig_backend == .stage1) {
@@ -1231,3 +1232,17 @@ test "modRem with zero divisor" {
         _ = zeros[0];
     }
 }
+
+test "array operands to shuffle are coerced to vectors" {
+    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
+
+    const mask = [5]i32{ -1, 0, 1, 2, 3 };
+
+    var a = [5]u32{ 3, 5, 7, 9, 0 };
+    var b = @shuffle(u32, a, @splat(5, @as(u24, 0)), mask);
+    try expectEqual([_]u32{ 0, 3, 5, 7, 9 }, b);
+}