[clang] [HLSL] Implement the `lit` intrinsic (PR #134171)

[Kaitlin Peng via cfe-commits]

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+// RUN: not %clang_dxc -enable-16bit-types -T cs_6_0 -HV 202x %s 2>&1  | FileCheck %s -DTEST_TYPE=half
+// RUN: not %clang_dxc -enable-16bit-types -T cs_6_0 -HV 202x %s 2>&1  | FileCheck %s -DTEST_TYPE=int16_t
+// RUN: not %clang_dxc -enable-16bit-types -T cs_6_0 -HV 202x %s 2>&1  | FileCheck %s -DTEST_TYPE=uint16_t
+
+// check we error on 16 bit type if shader model is too old
+// CHECK: '-enable-16bit-types' option requires target HLSL Version >= 2018 and shader model >= 6.2, but HLSL Version is 'hlsl202x' and shader model is '6.0'
+vector<TEST_TYPE,4> test_error(TEST_TYPE p0) {
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kmpeng wrote:

Code updated.

https://github.com/llvm/llvm-project/pull/134171