llvm/test/CodeGen/AArch64/sms-unpipeline-insts2.mir

# RUN: llc --verify-machineinstrs -mtriple=aarch64 -o - %s -run-pass pipeliner -aarch64-enable-pipeliner -pipeliner-enable-copytophi=0 -debug-only=pipeliner 2>&1 | FileCheck %s
# REQUIRES: asserts

# An acceptable loop by pipeliner TBB == LoopBB, FBB == ExitBB, Compare and branch
# CHECK: SU([[SU0:[0-9]+]]):   [[V0:%[0-9]+]]:gpr64common = SUBXri [[V1:%[0-9]+]]:gpr64common, 1, 0
# CHECK: Do not pipeline SU([[SU0:[0-9]+]])

--- |
  define dso_local void @func(ptr noalias nocapture noundef writeonly %a, ptr nocapture noundef readonly %b, i32 noundef %n) local_unnamed_addr #0 {
  entry:
    %or.cond = icmp ult i32 %n, 2
    br i1 %or.cond, label %for.end, label %for.body.preheader
  
  for.body.preheader:                               ; preds = %entry
    %i.07 = add i32 %n, -1
    %0 = sext i32 %i.07 to i64
    br label %for.body
  
  for.body:                                         ; preds = %for.body.preheader, %for.body
    %indvars.iv = phi i64 [ %0, %for.body.preheader ], [ %indvars.iv.next, %for.body ]
    %1 = shl nsw i64 %indvars.iv, 2
    %scevgep = getelementptr i8, ptr %b, i64 %1
    %2 = load float, ptr %scevgep, align 4
    %add = fadd float %2, 1.000000e+00
    %3 = shl nsw i64 %indvars.iv, 2
    %scevgep11 = getelementptr i8, ptr %a, i64 %3
    store float %add, ptr %scevgep11, align 4
    %indvars.iv.next = add nsw i64 %indvars.iv, -1
    %4 = add i64 %indvars.iv, -1
    %5 = and i64 %4, 4294967295
    %tobool.not = icmp eq i64 %5, 0
    br i1 %tobool.not, label %for.end, label %for.body
  
  for.end:                                          ; preds = %for.body, %entry
    ret void
  }
  
...
---
name:            func
tracksRegLiveness: true
liveins:
  - { reg: '$x0', virtual-reg: '%3' }
  - { reg: '$x1', virtual-reg: '%4' }
  - { reg: '$w2', virtual-reg: '%5' }
body:             |
  bb.0.entry:
    liveins: $x0, $x1, $w2
  
    %5:gpr32common = COPY $w2
    %4:gpr64common = COPY $x1
    %3:gpr64common = COPY $x0
    dead $wzr = SUBSWri %5, 2, 0, implicit-def $nzcv
    Bcc 3, %bb.3, implicit $nzcv
    B %bb.1
  
  bb.1.for.body.preheader:
    %7:gpr32common = SUBWri %5, 1, 0
    %9:gpr64all = IMPLICIT_DEF
    %8:gpr64 = SUBREG_TO_REG 0, killed %7, %subreg.sub_32
    %10:gpr64 = SBFMXri killed %8, 0, 31
    %0:gpr64all = COPY %10
    %12:fpr32 = FMOVSi 112
  
  bb.2.for.body:
    successors: %bb.3(0x04000000), %bb.2(0x7c000000)
  
    %1:gpr64common = PHI %0, %bb.1, %2, %bb.2
    %11:fpr32 = LDRSroX %4, %1, 0, 1 :: (load (s32) from %ir.scevgep)
    %13:fpr32 = nofpexcept FADDSrr killed %11, %12, implicit $fpcr
    STRSroX killed %13, %3, %1, 0, 1 :: (store (s32) into %ir.scevgep11)
    %14:gpr64common = SUBXri %1, 1, 0
    %2:gpr64all = COPY %14
    %15:gpr32 = COPY %14.sub_32
    CBNZW killed %15, %bb.2
    B %bb.3
  
  bb.3.for.end:
    RET_ReallyLR

...