optnone-llc.ll 2.46 KB
; RUN: llc -O1 -debug %s -o /dev/null 2>&1 | FileCheck %s --check-prefix=LLC-Ox
; RUN: llc -O2 -debug %s -o /dev/null 2>&1 | FileCheck %s --check-prefix=LLC-Ox
; RUN: llc -O3 -debug %s -o /dev/null 2>&1 | FileCheck %s --check-prefix=LLC-Ox
; RUN: llc -misched-postra -debug %s -o /dev/null 2>&1 | FileCheck %s --check-prefix=LLC-MORE
; RUN: llc -O1 -debug-only=isel %s -o /dev/null 2>&1 | FileCheck %s --check-prefix=FAST
; RUN: llc -O1 -debug-only=isel -fast-isel=false %s -o /dev/null 2>&1 | FileCheck %s --check-prefix=NOFAST

; REQUIRES: asserts, default_triple

; This test verifies that we don't run Machine Function optimizations
; on optnone functions, and that we can turn off FastISel.

; Function Attrs: noinline optnone
define i32 @_Z3fooi(i32 %x) #0 {
entry:
  %x.addr = alloca i32, align 4
  store i32 %x, i32* %x.addr, align 4
  br label %while.cond

while.cond:                                       ; preds = %while.body, %entry
  %0 = load i32, i32* %x.addr, align 4
  %dec = add nsw i32 %0, -1
  store i32 %dec, i32* %x.addr, align 4
  %tobool = icmp ne i32 %0, 0
  br i1 %tobool, label %while.body, label %while.end

while.body:                                       ; preds = %while.cond
  br label %while.cond

while.end:                                        ; preds = %while.cond
  ret i32 0
}

attributes #0 = { optnone noinline }

; Nothing that runs at -O0 gets skipped.
; LLC-O0-NOT: Skipping pass

; Machine Function passes run at -O1 and higher.
; LLC-Ox-DAG: Skipping pass 'Branch Probability Basic Block Placement'
; LLC-Ox-DAG: Skipping pass 'CodeGen Prepare'
; LLC-Ox-DAG: Skipping pass 'Control Flow Optimizer'
; LLC-Ox-DAG: Skipping pass 'Machine code sinking'
; LLC-Ox-DAG: Skipping pass 'Machine Common Subexpression Elimination'
; LLC-Ox-DAG: Skipping pass 'Shrink Wrapping analysis'
; LLC-Ox-DAG: Skipping pass 'Machine Copy Propagation Pass'
; LLC-Ox-DAG: Skipping pass 'Machine Instruction Scheduler'
; LLC-Ox-DAG: Skipping pass 'Machine Loop Invariant Code Motion'
; LLC-Ox-DAG: Skipping pass 'Optimize machine instruction PHIs'
; LLC-Ox-DAG: Skipping pass 'Peephole Optimizations'
; LLC-Ox-DAG: Skipping pass 'Post{{.*}}RA{{.*}}{{[Ss]}}cheduler'
; LLC-Ox-DAG: Skipping pass 'Remove dead machine instructions'
; LLC-Ox-DAG: Skipping pass 'Tail Duplication'

; Alternate post-RA scheduler.
; LLC-MORE: Skipping pass 'PostRA Machine Instruction Scheduler'

; Selectively disable FastISel for optnone functions.
; FAST:   FastISel is enabled
; NOFAST: FastISel is disabled