Remove jumps over empty blocks.

tests_lit/llvm2ice_tests/branch-opt.ll

 ; Tests the branch optimizations under O2 (against a lack of
 ; optimizations under Om1).
 
 ; RUN: %if --need=target_X8632 --command %p2i --filetype=obj --disassemble \
 ; RUN:   --target x8632 -i %s --args -O2 \
 ; RUN:   | %if --need=target_X8632 --command FileCheck --check-prefix=O2 %s
 
 ; RUN: %if --need=target_X8632 --command %p2i --filetype=obj --disassemble \
 ; RUN:   --target x8632 -i %s --args -Om1 \
 ; RUN:   | %if --need=target_X8632 --command FileCheck --check-prefix=OM1 %s
@@ skipping 151 matching lines @@
 ; ARM32OM1-LABEL: testCondTargetNextBlock
 ; ARM32OM1: cmp {{.*}}, #123
 ; ARM32OM1: movge {{.*}}, #1
 ; ARM32OM1: cmp {{.*}}, #0
 ; ARM32OM1: bne
 ; ARM32OM1: b
 ; ARM32OM1: bl
 ; ARM32OM1: bx lr
 ; ARM32OM1: bl
 ; ARM32OM1: bx lr
+
+; Unconditional branches to the block after a contracted block should be
+; removed.
+define void @testUncondToBlockAfterContract() {
+entry:
+  call void @dummy()
+  br label %target
+contract:
+  br label %target
+target:
+  call void @dummy()
+  ret void
+}
+
+; O2-LABEL: testUncondToBlockAfterContract
+; O2: call
+; There will be nops for bundle align to end (for NaCl), but there should
+; not be a branch.
+; O2-NOT: j
+; O2: call
+
+; OM1-LABEL: testUncondToBlockAfterContract
+; OM1: call
+; OM1-NEXT: jmp
+; OM1: call
+
+; ARM32O2-LABEL: testUncondToBlockAfterContract
+; ARM32O2: bl {{.*}} dummy
+; ARM32O2-NEXT: bl {{.*}} dummy
+
+; ARM32OM1-LABEL: testUncondToBlockAfterContract
+; ARM32OM1: bl {{.*}} dummy
+; ARM32OM1-NEXT: b
+; ARM32OM1-NEXT: bl {{.*}} dummy