[clang] [Clang][Unittest] Support for `target` update directive and `from` clause in clang unittests (PR #150580)

[Shilei Tian via cfe-commits]

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@@ -2770,6 +2770,140 @@ void x() {
   EXPECT_TRUE(notMatchesWithOpenMP(Source2, Matcher));
 }
 
+TEST(ASTMatchersTestOpenMP, OMPTargetUpdateDirective_From) {
+  auto Matcher = stmt(ompTargetUpdateDirective());
+
+  StringRef Source0 = R"(
+    void foo() {
+      int arr[8];
+      #pragma omp target update from(arr[0:8:2])
+      ;
+    }
+  )";
+  EXPECT_TRUE(matchesWithOpenMP(Source0, Matcher));
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shiltian wrote:

Not exactly align with what I had in mind but it can be improved later.

https://github.com/llvm/llvm-project/pull/150580