llvm-project/llvm/test/Transforms/LoopUnroll/full-unroll-bad-cost.ll

60 lines
1.4 KiB
LLVM

; RUN: opt -S -loop-unroll < %s | FileCheck %s
; RUN: opt < %s -passes='require<opt-remark-emit>,loop(unroll-full)' -S | FileCheck %s
; LLVM should not try to fully unroll this loop.
declare void @f()
declare void @g()
declare void @h()
define void @trivial_loop() {
; CHECK-LABEL: @trivial_loop(
entry:
br label %loop
loop:
%idx = phi i32 [ 0, %entry ], [ %idx.inc, %loop ]
%idx.inc = add i32 %idx, 1
call void @f()
call void @g()
call void @h()
call void @f()
call void @g()
call void @h()
call void @f()
call void @g()
call void @h()
call void @f()
call void @g()
call void @h()
call void @f()
call void @g()
call void @h()
%be = icmp slt i32 %idx, 268435456
br i1 %be, label %loop, label %exit
; CHECK: loop:
; CHECK-NEXT: %idx = phi i32 [ 0, %entry ], [ %idx.inc, %loop ]
; CHECK-NEXT: %idx.inc = add i32 %idx, 1
; CHECK-NEXT: call void @f()
; CHECK-NEXT: call void @g()
; CHECK-NEXT: call void @h()
; CHECK-NEXT: call void @f()
; CHECK-NEXT: call void @g()
; CHECK-NEXT: call void @h()
; CHECK-NEXT: call void @f()
; CHECK-NEXT: call void @g()
; CHECK-NEXT: call void @h()
; CHECK-NEXT: call void @f()
; CHECK-NEXT: call void @g()
; CHECK-NEXT: call void @h()
; CHECK-NEXT: call void @f()
; CHECK-NEXT: call void @g()
; CHECK-NEXT: call void @h()
; CHECK-NEXT: %be = icmp slt i32 %idx, 268435456
; CHECK-NEXT: br i1 %be, label %loop, label %exit
exit:
ret void
}