[ConstraintElimination] Add additional tests with uncond branches.

(cherry-picked from 2229674)

Author: fhahn

llvm/test/Transforms/ConstraintElimination/assumes.ll

@@ -180,6 +180,28 @@ exit:
   ret i1 %c.2
 }
 
+define i1 @assume_dominates_successor_with_may_unwind_call_before_assume_uncond_branch(i16 %a) {
+; CHECK-LABEL: @assume_dominates_successor_with_may_unwind_call_before_assume_uncond_branch(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    call void @may_unwind()
+; CHECK-NEXT:    [[C_1:%.*]] = icmp eq i16 [[A:%.*]], 0
+; CHECK-NEXT:    call void @llvm.assume(i1 [[C_1]])
+; CHECK-NEXT:    br label [[EXIT:%.*]]
+; CHECK:       exit:
+; CHECK-NEXT:    [[C_2:%.*]] = icmp eq i16 [[A]], 0
+; CHECK-NEXT:    ret i1 [[C_2]]
+;
+entry:
+  call void @may_unwind()
+  %c.1 = icmp eq i16 %a, 0
+  call void @llvm.assume(i1 %c.1)
+  br label %exit
+
+exit:
+  %c.2 = icmp eq i16 %a, 0
+  ret i1 %c.2
+}
+
 define i1 @assume_single_bb(i8 %a, i8 %b, i1 %c) {
 ; CHECK-LABEL: @assume_single_bb(
 ; CHECK-NEXT:    [[ADD_1:%.*]] = add nuw nsw i8 [[A:%.*]], 1
@@ -517,4 +539,3 @@ define i1 @all_uses_after_assume(i8 %a, i8 %b, i1 %c) {
   %res.2 = xor i1 %res.1, %c.2
   ret i1 %res.2
 }
-

llvm/test/Transforms/ConstraintElimination/dom.ll

@@ -34,6 +34,69 @@ bb2:
   ret i1 %c.3
 }
 
+define i1 @test_chain_1(i8 %x) {
+; CHECK-LABEL: @test_chain_1(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[C_1:%.*]] = icmp ule i8 [[X:%.*]], 10
+; CHECK-NEXT:    br i1 [[C_1]], label [[THEN:%.*]], label [[ELSE:%.*]]
+; CHECK:       then:
+; CHECK-NEXT:    [[C_2:%.*]] = icmp ule i8 [[X]], 10
+; CHECK-NEXT:    call void @use(i1 true)
+; CHECK-NEXT:    br label [[EXIT:%.*]]
+; CHECK:       else:
+; CHECK-NEXT:    br label [[EXIT]]
+; CHECK:       exit:
+; CHECK-NEXT:    [[C_3:%.*]] = icmp ugt i8 [[X]], 10
+; CHECK-NEXT:    ret i1 [[C_3]]
+;
+entry:
+  %c.1 = icmp ule i8 %x, 10
+  br i1 %c.1, label %then, label %else
+
+then:
+  %c.2 = icmp ule i8 %x, 10
+  call void @use(i1 %c.2)
+  br label %exit
+
+else:
+  br label %exit
+
+exit:
+  %c.3 = icmp ugt i8 %x, 10
+  ret i1 %c.3
+}
+
+define i1 @test_chain_2(i8 %x) {
+; CHECK-LABEL: @test_chain_2(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[C_1:%.*]] = icmp ule i8 [[X:%.*]], 10
+; CHECK-NEXT:    br i1 [[C_1]], label [[THEN:%.*]], label [[ELSE:%.*]]
+; CHECK:       then:
+; CHECK-NEXT:    br label [[EXIT:%.*]]
+; CHECK:       else:
+; CHECK-NEXT:    [[C_2:%.*]] = icmp ule i8 [[X]], 10
+; CHECK-NEXT:    call void @use(i1 false)
+; CHECK-NEXT:    br label [[EXIT]]
+; CHECK:       exit:
+; CHECK-NEXT:    [[C_3:%.*]] = icmp ugt i8 [[X]], 10
+; CHECK-NEXT:    ret i1 [[C_3]]
+;
+entry:
+  %c.1 = icmp ule i8 %x, 10
+  br i1 %c.1, label %then, label %else
+
+then:
+  br label %exit
+
+else:
+  %c.2 = icmp ule i8 %x, 10
+  call void @use(i1 %c.2)
+  br label %exit
+
+exit:
+  %c.3 = icmp ugt i8 %x, 10
+  ret i1 %c.3
+}
 
 define i1 @test2(i8 %x) {
 ; CHECK-LABEL: @test2(
@@ -62,7 +125,6 @@ bb2:
   br label %bb1
 }
 
-
 ; Test cases where the true/false successors are not domianted by the conditional branching block.
 define i1 @test3(i8 %x, i1 %c) {
 ; CHECK-LABEL: @test3(