From 4e958a532b38a0d504457c40982eb02ec8dc0f4e Mon Sep 17 00:00:00 2001
From: Scott McMurray <scottmcm@users.noreply.github.com>
Date: Wed, 2 Aug 2023 12:45:52 -0700
Subject: [PATCH] Add a new `compare_bytes` intrinsic instead of calling
 `memcmp` directly

---
 src/intrinsics/mod.rs | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/src/intrinsics/mod.rs b/src/intrinsics/mod.rs
index e3006b253b7..dcb080b9ec1 100644
--- a/src/intrinsics/mod.rs
+++ b/src/intrinsics/mod.rs
@@ -1155,6 +1155,19 @@ fn codegen_regular_intrinsic_call<'tcx>(
             ret.write_cvalue(fx, CValue::by_val(is_eq_value, ret.layout()));
         }
 
+        sym::compare_bytes => {
+            intrinsic_args!(fx, args => (lhs_ptr, rhs_ptr, bytes_val); intrinsic);
+            let lhs_ptr = lhs_ptr.load_scalar(fx);
+            let rhs_ptr = rhs_ptr.load_scalar(fx);
+            let bytes_val = bytes_val.load_scalar(fx);
+
+            let params = vec![AbiParam::new(fx.pointer_type); 3];
+            let returns = vec![AbiParam::new(types::I32)];
+            let args = &[lhs_ptr, rhs_ptr, bytes_val];
+            let cmp = fx.lib_call("memcmp", params, returns, args)[0];
+            ret.write_cvalue(fx, CValue::by_val(cmp, ret.layout()));
+        }
+
         sym::const_allocate => {
             intrinsic_args!(fx, args => (_size, _align); intrinsic);