[JumpThreading] Add a test for D85023; NFC

diff --git a/llvm/test/Transforms/JumpThreading/thread-two-bbs-threshold.ll b/llvm/test/Transforms/JumpThreading/thread-two-bbs-threshold.ll
new file mode 100644 (file)
index 0000000..5650d8b
--- /dev/null
+++ b/llvm/test/Transforms/JumpThreading/thread-two-bbs-threshold.ll
@@ -0,0 +1,79 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt < %s -jump-threading -jump-threading-threshold=3 -S -verify | FileCheck %s
+
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+@a = global i32 0, align 4
+
+define void @foo(i32 %cond1, i32 %cond2) {
+; CHECK-LABEL: @foo(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[TOBOOL:%.*]] = icmp eq i32 [[COND1:%.*]], 0
+; CHECK-NEXT:    br i1 [[TOBOOL]], label [[BB_COND2:%.*]], label [[BB_F1:%.*]]
+; CHECK:       bb.f1:
+; CHECK-NEXT:    call void @f1()
+; CHECK-NEXT:    br label [[BB_COND2]]
+; CHECK:       bb.cond2:
+; CHECK-NEXT:    [[PTR:%.*]] = phi i32* [ null, [[BB_F1]] ], [ @a, [[ENTRY:%.*]] ]
+; CHECK-NEXT:    [[COND2_FR:%.*]] = freeze i32 [[COND2:%.*]]
+; CHECK-NEXT:    [[X:%.*]] = add i32 [[COND2_FR]], 1
+; CHECK-NEXT:    [[TOBOOL1:%.*]] = icmp eq i32 [[X]], 0
+; CHECK-NEXT:    br i1 [[TOBOOL1]], label [[BB_FILE:%.*]], label [[BB_F2:%.*]]
+; CHECK:       bb.f2:
+; CHECK-NEXT:    call void @f2()
+; CHECK-NEXT:    br label [[EXIT:%.*]]
+; CHECK:       bb.file:
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i32* [[PTR]], null
+; CHECK-NEXT:    br i1 [[CMP]], label [[BB_F4:%.*]], label [[BB_F3:%.*]]
+; CHECK:       bb.f3:
+; CHECK-NEXT:    call void @f3()
+; CHECK-NEXT:    br label [[EXIT]]
+; CHECK:       bb.f4:
+; CHECK-NEXT:    call void @f4()
+; CHECK-NEXT:    br label [[EXIT]]
+; CHECK:       exit:
+; CHECK-NEXT:    ret void
+;
+entry:
+  %tobool = icmp eq i32 %cond1, 0
+  br i1 %tobool, label %bb.cond2, label %bb.f1
+
+bb.f1:
+  call void @f1()
+  br label %bb.cond2
+
+bb.cond2:
+  %ptr = phi i32* [ null, %bb.f1 ], [ @a, %entry ]
+  %cond2.fr = freeze i32 %cond2
+  %x = add i32 %cond2.fr, 1
+  %tobool1 = icmp eq i32 %x, 0
+  br i1 %tobool1, label %bb.file, label %bb.f2
+
+bb.f2:
+  call void @f2()
+  br label %exit
+
+bb.file:
+  %cmp = icmp eq i32* %ptr, null
+  br i1 %cmp, label %bb.f4, label %bb.f3
+
+bb.f3:
+  call void @f3()
+  br label %exit
+
+bb.f4:
+  call void @f4()
+  br label %exit
+
+exit:
+  ret void
+}
+
+declare void @f1()
+
+declare void @f2()
+
+declare void @f3()
+
+declare void @f4()