Imported Upstream version 5.18.0.205

Former-commit-id: 7f59f7e792705db773f1caecdaa823092f4e2927

external/llvm/test/Transforms/RewriteStatepointsForGC/preprocess.ll

@@ -0,0 +1,63 @@
+; RUN: opt -rewrite-statepoints-for-gc -S < %s | FileCheck %s
+; RUN: opt -passes=rewrite-statepoints-for-gc -S < %s | FileCheck %s
+
+; Test to make sure we destroy LCSSA's single entry phi nodes before
+; running liveness
+
+declare void @consume(...) "gc-leaf-function"
+
+define void @test6(i64 addrspace(1)* %obj) gc "statepoint-example" {
+; CHECK-LABEL: @test6
+entry:
+  br label %next
+
+next:                                             ; preds = %entry
+; CHECK-LABEL: next:
+; CHECK-NEXT: gc.statepoint
+; CHECK-NEXT: gc.relocate
+; CHECK-NEXT: bitcast
+; CHECK-NEXT: @consume(i64 addrspace(1)* %obj.relocated.casted)
+; CHECK-NEXT: @consume(i64 addrspace(1)* %obj.relocated.casted)
+; Need to delete unreachable gc.statepoint call
+  %obj2 = phi i64 addrspace(1)* [ %obj, %entry ]
+  call void @foo() [ "deopt"() ]
+  call void (...) @consume(i64 addrspace(1)* %obj2)
+  call void (...) @consume(i64 addrspace(1)* %obj)
+  ret void
+}
+
+define void @test7() gc "statepoint-example" {
+; CHECK-LABEL: test7
+; CHECK-NOT: gc.statepoint
+; Need to delete unreachable gc.statepoint invoke - tested seperately given
+; a correct implementation could only remove the instructions, not the block
+  ret void
+
+unreached:                                        ; preds = %unreached
+  %obj = phi i64 addrspace(1)* [ null, %unreached ]
+  call void @foo() [ "deopt"() ]
+  call void (...) @consume(i64 addrspace(1)* %obj)
+  br label %unreached
+}
+
+define void @test8() gc "statepoint-example" personality i32 ()* undef {
+; CHECK-LABEL: test8
+; CHECK-NOT: gc.statepoint
+; Bound the last check-not
+  ret void
+
+unreached:                                        ; No predecessors!
+  invoke void @foo() [ "deopt"() ]
+; CHECK-LABEL: @foo
+          to label %normal_return unwind label %exceptional_return
+
+normal_return:                                    ; preds = %unreached
+  ret void
+
+exceptional_return:                               ; preds = %unreached
+  %landing_pad4 = landingpad { i8*, i32 }
+          cleanup
+  ret void
+}
+
+declare void @foo()