[clang] [llvm] [Clang] Add `__builtin_stack_address` (PR #148281)

[Matt Arsenault via llvm-commits]

================
@@ -0,0 +1,9 @@
+; RUN: not llc < %s -mtriple nvptx 2>&1 | FileCheck %s
+
+declare ptr @llvm.stackaddress.p0()
+
+define ptr @test() {
+; CHECK: STACKADDRESS is not supported on this target.
----------------
arsenm wrote:

Probably should also refer to the intrinsic by name, not the DAG operation. We're not consistent on this, but at least in this case it will always directly map back to the intrinsic 

https://github.com/llvm/llvm-project/pull/148281