[clang] [CIR] Upstream cir-canonicalize pass (PR #131891)

[Erich Keane via cfe-commits]

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@@ -0,0 +1,72 @@
+// RUN: cir-opt %s -cir-canonicalize -o - | FileCheck %s
+
+module {
+  cir.func @redundant_br() {
+    cir.br ^bb1
+  ^bb1:  // pred: ^bb0
+    %0 = cir.alloca !cir.int<u, 32>, !cir.ptr<!cir.int<u, 32>>, ["a", init] {alignment = 4 : i64}
+    %1 = cir.const #cir.int<4> : !cir.int<u, 32>
+    cir.store %1, %0 : !cir.int<u, 32>, !cir.ptr<!cir.int<u, 32>>
+    cir.br ^bb2
+  ^bb2:  // pred: ^bb1
+    cir.return
+  }
+  // CHECK:  cir.func @redundant_br() {
+  // CHECK-NOT: ^
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erichkeane wrote:

Instead of the CHECK-NOT, could we just do a CHECK-NEXT in these few places?

https://github.com/llvm/llvm-project/pull/131891