Add Om1 lowering with no optimizations

tests_lit/llvm2ice_tests/simple-arith.ll

-; RUIN: %llvm2ice -verbose inst %s | FileCheck %s
-; RUIN: %llvm2ice --verbose none %s | FileCheck --check-prefix=ERRORS %s
-; RUN: %llvm2iceinsts %s | %szdiff %s | FileCheck --check-prefix=DUMP %s
-; RUN: %llvm2iceinsts --pnacl %s | %szdiff %s \
-; RUN:                           | FileCheck --check-prefix=DUMP %s
-
-define i64 @add_args_i64(i64 %arg1, i64 %arg2) {
-entry:
-  %add = add i64 %arg2, %arg1
-  ret i64 %add
-}
-
-; Checks for verbose instruction output
-
-; CHECK: define i64 @add_args
-; CHECK: %add = add i64 %arg2, %arg1
-; CHECK-NEXT: ret i64 %add
-
-define i32 @add_args_i32(i32 %arg1, i32 %arg2) {
-entry:
-  %add = add i32 %arg2, %arg1
-  ret i32 %add
-}
-
-; Checks for emitted assembly
-
-; CHECK:      .globl add_args_i32
-; CHECK:      mov eax, dword ptr [esp+4]
-; CHECK-NEXT: mov ecx, dword ptr [esp+8]
-; CHECK-NEXT: add ecx, eax
-; CHECK-NEXT: mov eax, ecx
-; CHECK-NEXT: ret
-
-; ERRORS-NOT: ICE translation error
-; DUMP-NOT: SZ