Imported Upstream version 5.18.0.246

Former-commit-id: 0c7ce5b1a7851e13f22acfd379b7f9fb304e4833

external/llvm/test/Transforms/SimplifyCFG/switch-to-icmp.ll

@@ -0,0 +1,57 @@
+; RUN: opt -S -simplifycfg < %s | FileCheck %s
+
+define zeroext i1 @test1(i32 %x) nounwind readnone ssp noredzone {
+entry:
+ switch i32 %x, label %lor.rhs [
+   i32 2, label %lor.end
+   i32 1, label %lor.end
+   i32 3, label %lor.end
+ ]
+
+lor.rhs:
+ br label %lor.end
+
+lor.end:
+ %0 = phi i1 [ true, %entry ], [ false, %lor.rhs ], [ true, %entry ], [ true, %entry ]
+ ret i1 %0
+
+; CHECK-LABEL: @test1(
+; CHECK: %x.off = add i32 %x, -1
+; CHECK: %switch = icmp ult i32 %x.off, 3
+}
+
+define zeroext i1 @test2(i32 %x) nounwind readnone ssp noredzone {
+entry:
+ switch i32 %x, label %lor.rhs [
+   i32 0, label %lor.end
+   i32 1, label %lor.end
+ ]
+
+lor.rhs:
+ br label %lor.end
+
+lor.end:
+ %0 = phi i1 [ true, %entry ], [ false, %lor.rhs ], [ true, %entry ]
+ ret i1 %0
+
+; CHECK-LABEL: @test2(
+; CHECK: %switch = icmp ult i32 %x, 2
+}
+
+define i32 @test3(i1 %flag) {
+entry:
+ switch i1 %flag, label %bad [
+   i1 true, label %good
+   i1 false, label %good
+ ]
+
+good:
+ ret i32 0
+
+bad:
+ ret i32 1
+
+; CHECK-LABEL: @test3(
+; CHECK: entry:
+; CHECK-NEXT: ret i32 0
+}