From c42bc99683cdaf964bf9e9e45523cf210471a528 Mon Sep 17 00:00:00 2001
From: Laurence Tratt <laurie@tratt.net>
Date: Sun, 26 Jan 2025 09:00:59 +0000
Subject: [PATCH] Don't abort compilation for LLVM hint functions.

---
 ykrt/src/compile/jitc_yk/codegen/x64/mod.rs | 40 +++++++++++++++++++--
 1 file changed, 37 insertions(+), 3 deletions(-)

diff --git a/ykrt/src/compile/jitc_yk/codegen/x64/mod.rs b/ykrt/src/compile/jitc_yk/codegen/x64/mod.rs
index 6eb49899a..9d9c16aa5 100644
--- a/ykrt/src/compile/jitc_yk/codegen/x64/mod.rs
+++ b/ykrt/src/compile/jitc_yk/codegen/x64/mod.rs
@@ -1499,9 +1499,15 @@ impl<'a> Assemble<'a> {
             .collect::<Vec<_>>();
 
         // unwrap safe on account of linker symbol names not containing internal NULL bytes.
-        let va = symbol_to_ptr(self.m.func_decl(func_decl_idx).name())
-            .map_err(|e| CompilationError::General(e.to_string()))?;
-        self.emit_call(iidx, fty, Some(va), None, &args)
+        match self.m.func_decl(func_decl_idx).name() {
+            "llvm.assume" => Ok(()),
+            "llvm.lifetime.start.p0" => Ok(()),
+            "llvm.lifetime.end.p0" => Ok(()),
+            x => {
+                let va = symbol_to_ptr(x).map_err(|e| CompilationError::General(e.to_string()))?;
+                self.emit_call(iidx, fty, Some(va), None, &args)
+            }
+        }
     }
 
     /// Codegen a indirect call.
@@ -3865,6 +3871,34 @@ mod tests {
         );
     }
 
+    #[test]
+    fn cg_call_hints() {
+        codegen_and_test(
+            "
+             func_decl llvm.assume (i1)
+             func_decl llvm.lifetime.start.p0 (i64, ptr)
+             func_decl llvm.lifetime.end.p0 (i64, ptr)
+             entry:
+               %0: i1 = param 0
+               %1: ptr = param 1
+               call @llvm.assume(%0)
+               call @llvm.lifetime.start.p0(16i64, %1)
+               call @llvm.lifetime.end.p0(16i64, %1)
+               %5: ptr = ptr_add %1, 1
+               black_box %5
+            ",
+            "
+               ...
+               ; call @llvm.assume(%0)
+               ; call @llvm.lifetime.start.p0(16i64, %1)
+               ; call @llvm.lifetime.end.p0(16i64, %1)
+               ; %5: ...
+               ...
+            ",
+            false,
+        );
+    }
+
     #[test]
     fn cg_eq() {
         codegen_and_test(