diff --git a/src/irgen.jl b/src/irgen.jl
index 919d9793..c8e2d75d 100644
--- a/src/irgen.jl
+++ b/src/irgen.jl
@@ -265,11 +265,14 @@ function emit_exception!(builder, name, inst)
     # report the exception
     if Base.JLOptions().debug_level >= 1
         name = globalstring_ptr!(builder, name, "exception")
-        if Base.JLOptions().debug_level == 1
+        c = if Base.JLOptions().debug_level == 1
             call!(builder, Runtime.get(:report_exception), [name])
         else
             call!(builder, Runtime.get(:report_exception_name), [name])
         end
+        callsite_attribute!(c, (
+            LLVM.EnumAttribute("inaccessiblememonly", 0; ctx),
+            LLVM.EnumAttribute("writeonly", 0; ctx)))
     end
 
     # report each frame
@@ -287,7 +290,10 @@ function emit_exception!(builder, name, inst)
     end
 
     # signal the exception
-    call!(builder, Runtime.get(:signal_exception))
+    c = call!(builder, Runtime.get(:signal_exception))
+    callsite_attribute!(c, (
+        LLVM.EnumAttribute("inaccessiblememonly", 0; ctx),
+        LLVM.EnumAttribute("writeonly", 0; ctx)))
 
     emit_trap!(job, builder, mod, inst)
 end
diff --git a/src/utils.jl b/src/utils.jl
index f3190440..bbed9836 100644
--- a/src/utils.jl
+++ b/src/utils.jl
@@ -113,3 +113,10 @@ macro unlocked(ex)
     end
     esc(combinedef(def))
 end
+
+function callsite_attribute!(call, attributes)
+    # TODO: Make a nice API for this in LLVM.jl
+    for attribute in attributes
+        LLVM.API.LLVMAddCallSiteAttribute(call, LLVM.API.LLVMAttributeFunctionIndex, attribute)
+    end
+end