Subzero ARM: do lowerIcmp, lowerBr, and a bit of lowerCall.

tests_lit/llvm2ice_tests/branch-opt.ll

 ; Tests the branch optimizations under O2 (against a lack of
 ; optimizations under Om1).
 
-; RUN: %p2i --filetype=obj --disassemble -i %s --args -O2 \
-; RUN:   | FileCheck --check-prefix=O2 %s
-; RUN: %p2i --filetype=obj --disassemble -i %s --args -Om1 \
-; RUN:   | FileCheck --check-prefix=OM1 %s
+; 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
+
+; TODO(jvoung): Stop skipping unimplemented parts (via --skip-unimplemented)
+; once enough infrastructure is in. Also, switch to --filetype=obj
+; when possible.
+; Also test Om1 when addProlog is done.
+; RUN: %if --need=target_ARM32 --command %p2i --filetype=asm --assemble \
+; RUN:   --disassemble --target arm32 -i %s --args -O2 --skip-unimplemented \
+; RUN:   | %if --need=target_ARM32 --command FileCheck --check-prefix ARM32O2 %s
 
 declare void @dummy()
 
 ; An unconditional branch to the next block should be removed.
 define void @testUncondToNextBlock() {
 entry:
   call void @dummy()
   br label %next
 next:
   call void @dummy()
   ret void
 }
 ; O2-LABEL: testUncondToNextBlock
 ; 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: testUncondToNextBlock
 ; OM1: call
 ; OM1-NEXT: jmp
 ; OM1: call
 
+; ARM32O2-LABEL: testUncondToNextBlock
+; ARM32O2: bl {{.*}} dummy
+; ARM32O2-NEXT: bl {{.*}} dummy
+
 ; For a conditional branch with a fallthrough to the next block, the
 ; fallthrough branch should be removed.
 define void @testCondFallthroughToNextBlock(i32 %arg) {
 entry:
   %cmp = icmp sge i32 %arg, 123
   br i1 %cmp, label %target, label %fallthrough
 fallthrough:
   call void @dummy()
   ret void
 target:
@@ skipping 13 matching lines @@
 ; OM1: cmp {{.*}},0x7b
 ; OM1: setge
 ; OM1: cmp
 ; OM1: jne
 ; OM1: jmp
 ; OM1: call
 ; OM1: ret
 ; OM1: call
 ; OM1: ret
 
+; Note that compare and branch folding isn't implemented yet (unlike x86-32).
+; ARM32O2-LABEL: testCondFallthroughToNextBlock
+; ARM32O2: cmp {{.*}}, #123
+; ARM32O2-NEXT: movge {{.*}}, #1
+; ARM32O2-NEXT: cmp {{.*}}, #0
+; ARM32O2-NEXT: bne
+; ARM32O2-NEXT: bl 0
+; ARM32O2-NEXT: bx lr
+; ARM32O2-NEXT: bl 0
+; ARM32O2-NEXT: bx lr
+
 ; For a conditional branch with the next block as the target and a
 ; different block as the fallthrough, the branch condition should be
 ; inverted, the fallthrough block changed to the target, and the
 ; branch to the next block removed.
 define void @testCondTargetNextBlock(i32 %arg) {
 entry:
   %cmp = icmp sge i32 %arg, 123
   br i1 %cmp, label %fallthrough, label %target
 fallthrough:
   call void @dummy()
@@ skipping 14 matching lines @@
 ; OM1-LABEL: testCondTargetNextBlock
 ; OM1: cmp {{.*}},0x7b
 ; OM1: setge
 ; OM1: cmp
 ; OM1: jne
 ; OM1: jmp
 ; OM1: call
 ; OM1: ret
 ; OM1: call
 ; OM1: ret
+
+; Note that compare and branch folding isn't implemented yet
+; (compared to x86-32).
+; ARM32O2-LABEL: testCondTargetNextBlock
+; ARM32O2: cmp {{.*}}, #123
+; ARM32O2-NEXT: movge {{.*}}, #1
+; ARM32O2-NEXT: cmp {{.*}}, #0
+; ARM32O2-NEXT: beq
+; ARM32O2-NEXT: bl
+; ARM32O2-NEXT: bx lr
+; ARM32O2-NEXT: bl
+; ARM32O2-NEXT: bx lr