[clang] [CIR][NEON] Add lowering for `vnegd_s64` and `vnegh_f16` (PR #180597)

[Andy Kaylor via cfe-commits]

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@@ -0,0 +1,28 @@
+// REQUIRES: aarch64-registered-target
+
+// RUN:                   %clang_cc1 -triple arm64-none-linux-gnu -target-feature +fullfp16 -disable-O0-optnone           -emit-llvm -o - %s | opt -S -passes=mem2reg             | FileCheck %s --check-prefixes=LLVM
+// RUN: %if cir-enabled %{%clang_cc1 -triple arm64-none-linux-gnu -target-feature +fullfp16 -disable-O0-optnone -fclangir -emit-llvm -o - %s | opt -S -passes=mem2reg,simplifycfg | FileCheck %s --check-prefixes=LLVM %}
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andykaylor wrote:

Why is simplifycfg needed in the CIR case?

https://github.com/llvm/llvm-project/pull/180597