compiler: add @memmove builtin

1 files changed, 14 insertions, 1 deletions

diff --git a/src/codegen/c.zig b/src/codegen/c.zig
index 2aee078b11..e7883b9def 100644
--- a/src/codegen/c.zig
+++ b/src/codegen/c.zig
@@ -3349,6 +3349,7 @@ fn genBodyInner(f: *Function, body: []const Air.Inst.Index) error{ AnalysisFail,
             .memset           => try airMemset(f, inst, false),
             .memset_safe      => try airMemset(f, inst, true),
             .memcpy           => try airMemcpy(f, inst),
+            .memmove          => try airMemmove(f, inst),
             .set_union_tag    => try airSetUnionTag(f, inst),
             .get_union_tag    => try airGetUnionTag(f, inst),
             .clz              => try airUnBuiltinCall(f, inst, air_datas[@intFromEnum(inst)].ty_op.operand, "clz", .bits),
@@ -6976,6 +6977,14 @@ fn airMemset(f: *Function, inst: Air.Inst.Index, safety: bool) !CValue {
 }
 
 fn airMemcpy(f: *Function, inst: Air.Inst.Index) !CValue {
+    return copyOp(f, inst, .memcpy);
+}
+
+fn airMemmove(f: *Function, inst: Air.Inst.Index) !CValue {
+    return copyOp(f, inst, .memmove);
+}
+
+fn copyOp(f: *Function, inst: Air.Inst.Index, op: enum { memcpy, memmove }) !CValue {
     const pt = f.object.dg.pt;
     const zcu = pt.zcu;
     const bin_op = f.air.instructions.items(.data)[@intFromEnum(inst)].bin_op;
@@ -6990,7 +6999,11 @@ fn airMemcpy(f: *Function, inst: Air.Inst.Index) !CValue {
         try writeArrayLen(f, writer, dest_ptr, dest_ty);
         try writer.writeAll(" != 0) ");
     }
-    try writer.writeAll("memcpy(");
+    const function_paren = switch (op) {
+        .memcpy => "memcpy(",
+        .memmove => "memmove(",
+    };
+    try writer.writeAll(function_paren);
     try writeSliceOrPtr(f, writer, dest_ptr, dest_ty);
     try writer.writeAll(", ");
     try writeSliceOrPtr(f, writer, src_ptr, src_ty);