diff options
Diffstat (limited to 'test/Transforms/LoopUnswitch/trivial-unswitch.ll')
| -rw-r--r-- | test/Transforms/LoopUnswitch/trivial-unswitch.ll | 46 |
1 files changed, 45 insertions, 1 deletions
diff --git a/test/Transforms/LoopUnswitch/trivial-unswitch.ll b/test/Transforms/LoopUnswitch/trivial-unswitch.ll index db3328278dae..2def5b6f0334 100644 --- a/test/Transforms/LoopUnswitch/trivial-unswitch.ll +++ b/test/Transforms/LoopUnswitch/trivial-unswitch.ll @@ -44,4 +44,48 @@ loop_exit: ret i32 0 } -declare void @some_func() noreturn
\ No newline at end of file + +; We will not be able trivially unswitch on the SwitchInst, as its input +; is a constant. However, since its a constant we should be able to figure +; out that the switch can be folded into a unconditional branch to %continue. +; Then we unswitch on the br inst in %continue. +; +; CHECK: define i32 @test2( +; This is an indication that the loop has been unswitched on %cond1. +; CHECK: br i1 %cond1, label %..split_crit_edge, label %.loop_exit.split_crit_edge + +; CHECK: ..split_crit_edge: ; preds = %0 +; CHECK: br label %.split + +; CHECK: .split: ; preds = %..split_crit_edge +; CHECK: br label %loop_begin + +; CHECK: loop_begin: ; preds = %do_something, %.split +; CHECK: switch i32 + +; CHECK: continue: ; preds = %loop_begin +; CHECK: %var_val = load i32, i32* %var +; CHECK: br i1 true, label %do_something, label %loop_exit + +define i32 @test2(i32* %var, i1 %cond1) { + br label %loop_begin + +loop_begin: + switch i32 1, label %continue [ + i32 0, label %loop_exit + i32 1, label %continue + ] + +continue: + %var_val = load i32, i32* %var + br i1 %cond1, label %do_something, label %loop_exit + +do_something: + call void @some_func() noreturn nounwind + br label %loop_begin + +loop_exit: + ret i32 0 +} + +declare void @some_func() noreturn |