[clang] [CIR] Add math and builtin intrinsics support (PR #175233)

[Hendrik Hübner via cfe-commits]

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@@ -27,29 +34,38 @@ void testMemset(void *dst, int val, unsigned long size) {
 double fabs(double);
 double testFabs(double x) {
   return fabs(x);
-  // CHECK: cir.call @fabs
+  // CHECK: cir.fabs %{{.+}} : !cir.double
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HendrikHuebner wrote:

Can you add the other checks here as well? 

https://github.com/llvm/llvm-project/pull/175233