Imported Upstream version 5.18.0.161

Former-commit-id: 4db48158d3a35497b8f118ab21b5f08ac3d86d98

external/llvm/test/CodeGen/Hexagon/loop-idiom/lcssa.ll

@@ -0,0 +1,46 @@
+; RUN: opt -hexagon-loop-idiom -loop-deletion -gvn -S < %s
+; REQUIRES: asserts
+
+; This tests that the HexagonLoopIdiom pass does not mark LCSSA information
+; as preserved. The pass calls SimplifyInstruction is a couple of places,
+; which can invalidate LCSSA. Specifically, the uses of a LCSSA phi variable
+; are replaced by the incoming value.
+
+define hidden void @test() local_unnamed_addr #0 {
+entry:
+  br label %if.then63
+
+if.then63:
+  br i1 undef, label %do.body311, label %if.end375
+
+do.body311:
+  br i1 undef, label %do.end318, label %do.body311
+
+do.end318:
+  br i1 undef, label %if.end322, label %if.end375
+
+if.end322:
+  %sub325 = sub i32 undef, undef
+  br i1 undef, label %do.end329, label %do.body311
+
+do.end329:
+  %sub325.lcssa = phi i32 [ %sub325, %if.end322 ]
+  br label %do.body330
+
+do.body330:
+  %row_width.7 = phi i32 [ %sub325.lcssa, %do.end329 ], [ %dec334, %do.body330 ]
+  %sp.5 = phi i8* [ undef, %do.end329 ], [ %incdec.ptr331, %do.body330 ]
+  %dp.addr.5 = phi i8* [ undef, %do.end329 ], [ %incdec.ptr332, %do.body330 ]
+  %0 = load i8, i8* %sp.5, align 1
+  store i8 %0, i8* %dp.addr.5, align 1
+  %incdec.ptr332 = getelementptr inbounds i8, i8* %dp.addr.5, i32 1
+  %incdec.ptr331 = getelementptr inbounds i8, i8* %sp.5, i32 1
+  %dec334 = add i32 %row_width.7, -1
+  %cmp335 = icmp eq i32 %dec334, 0
+  br i1 %cmp335, label %if.end375, label %do.body330
+
+if.end375:
+  ret void
+}
+
+attributes #0 = { nounwind }