llvm/test/CodeGen/AArch64/machine-combiner-reassociate-accumulators.mir

# RUN: llc -run-pass=machine-combiner -mtriple=arm64-unknown-unknown %s -o - | FileCheck %s
# RUN: llc -run-pass=machine-combiner -mtriple=arm64-unknown-unknown -acc-max-width=2   %s -o -   | FileCheck %s  --check-prefix=NARROW-TREE
# RUN: llc -run-pass=machine-combiner -mtriple=arm64-unknown-unknown -acc-min-depth=100  %s -o -  | FileCheck %s  --check-prefix=NO-TREE

# A chain of UABAL instructions that can be reassociated for better ILP.
# Before the optimization, we accumulate in a single long chain.
# CHECK-LABEL: name:  uabal_accumulation
# CHECK:          [[START1:%.*]]:fpr128 = UABDLv4i16_v4i32
# CHECK:          [[START2:%.*]]:fpr128 = UABDLv4i16_v4i32
# CHECK:          [[START3:%.*]]:fpr128 = UABDLv4i16_v4i32
# CHECK:          [[A1:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[START1]] 
# CHECK:          [[B1:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[START2]] 
# CHECK:          [[C1:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[START3]] 
# CHECK:          [[A2:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[A1]] 
# CHECK:          [[B2:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[B1]] 
# CHECK:          [[C2:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[C1]] 
# CHECK:          [[PARTIAL_SUM:%.*]]:fpr128 = ADDv4i32 killed [[A2]], killed [[B2]]
# CHECK:          [[TOTAL_SUM:%.*]]:fpr128 = ADDv4i32 killed [[PARTIAL_SUM]], killed [[C2]]
# CHECK:          [[END:%.*]]:fpr32 = ADDVv4i32v killed [[TOTAL_SUM]]

# NARROW-TREE:    [[START1:%.*]]:fpr128 = UABDLv4i16_v4i32
# NARROW-TREE:    [[START2:%.*]]:fpr128 = UABDLv4i16_v4i32          
# NARROW-TREE:    [[A1:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[START1]]
# NARROW-TREE:    [[B1:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[START2]]
# NARROW-TREE:    [[A2:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[A1]]              
# NARROW-TREE:    [[B2:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[B1]]
# NARROW-TREE:    [[A3:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[A2]]
# NARROW-TREE:    [[B3:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[B2]]
# NARROW-TREE:    [[A4:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[A3]]
# NARROW-TREE:    [[PARTIAL_SUM:%.*]]:fpr128 = ADDv4i32 killed [[B3]], killed [[A4]]
# NARROW-TREE:    [[END:%.*]]:fpr32 = ADDVv4i32v killed [[PARTIAL_SUM]]  

# NO-TREE:        [[START1:%.*]]:fpr128 = UABDLv4i16_v4i32
# NO-TREE:        [[A1:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[START1]]
# NO-TREE:        [[A2:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[A1]]
# NO-TREE:        [[A3:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[A2]]
# NO-TREE:        [[A4:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[A3]]              
# NO-TREE:        [[A5:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[A4]]
# NO-TREE:        [[A6:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[A5]]
# NO-TREE:        [[A7:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[A6]]
# NO-TREE:        [[A8:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[A7]]
# NO-TREE:        [[END:%.*]]:fpr32 = ADDVv4i32v killed [[A8]]

---
name:            uabal_accumulation
body:             |
  bb.0.entry:
    liveins: $x0, $x1, $x2, $x3
  
    %3:gpr64 = COPY $x3
    %2:gpr64common = COPY $x2
    %1:gpr64 = COPY $x1
    %0:gpr64common = COPY $x0
    %4:fpr64 = LDRDui %0, 0 :: (load (s64))
    %5:fpr64 = LDRDui %2, 0 :: (load (s64))
    %6:gpr64common = ADDXrr %0, %1
    %7:gpr64common = ADDXrr %2, %3
    %8:fpr64 = LDRDui %6, 0 :: (load (s64))
    %9:fpr64 = LDRDui %7, 0 :: (load (s64))
    %10:fpr128 = UABDLv4i16_v4i32 killed %8, killed %9
    %11:fpr128 = UABALv4i16_v4i32 killed %10, killed %4, killed %5
    %12:gpr64common = ADDXrr %6, %1
    %13:gpr64common = ADDXrr %7, %3
    %14:fpr64 = LDRDui %12, 0 :: (load (s64))
    %15:fpr64 = LDRDui %13, 0 :: (load (s64))
    %16:fpr128 = UABALv4i16_v4i32 killed %11, killed %14, killed %15
    %17:gpr64common = ADDXrr %12, %1
    %18:gpr64common = ADDXrr %13, %3
    %19:fpr64 = LDRDui %17, 0 :: (load (s64))
    %20:fpr64 = LDRDui %18, 0 :: (load (s64))
    %21:fpr128 = UABALv4i16_v4i32 killed %16, killed %19, killed %20
    %22:gpr64common = ADDXrr %17, %1
    %23:gpr64common = ADDXrr %18, %3
    %24:fpr64 = LDRDui %22, 0 :: (load (s64))
    %25:fpr64 = LDRDui %23, 0 :: (load (s64))
    %26:fpr128 = UABALv4i16_v4i32 killed %21, killed %24, killed %25
    %27:gpr64common = ADDXrr %22, %1
    %28:gpr64common = ADDXrr %23, %3
    %29:fpr64 = LDRDui %27, 0 :: (load (s64))
    %30:fpr64 = LDRDui %28, 0 :: (load (s64))
    %31:fpr128 = UABALv4i16_v4i32 killed %26, killed %29, killed %30
    %32:gpr64common = ADDXrr %27, %1
    %33:gpr64common = ADDXrr %28, %3
    %34:fpr64 = LDRDui %32, 0 :: (load (s64))
    %35:fpr64 = LDRDui %33, 0 :: (load (s64))
    %36:fpr128 = UABALv4i16_v4i32 killed %31, killed %34, killed %35
    %37:gpr64common = ADDXrr %32, %1
    %38:gpr64common = ADDXrr %33, %3
    %39:fpr64 = LDRDui %37, 0 :: (load (s64))
    %40:fpr64 = LDRDui %38, 0 :: (load (s64))
    %41:fpr128 = UABALv4i16_v4i32 killed %36, killed %39, killed %40
    %42:gpr64common = ADDXrr %37, %1
    %43:gpr64common = ADDXrr %38, %3
    %44:fpr64 = LDRDui %42, 0 :: (load (s64))
    %45:fpr64 = LDRDui %43, 0 :: (load (s64))
    %46:fpr128 = UABALv4i16_v4i32 killed %41, killed %44, killed %45
    %47:fpr32 = ADDVv4i32v killed %46
    %48:fpr128 = IMPLICIT_DEF
    %49:fpr128 = INSERT_SUBREG %48, killed %47, %subreg.ssub
    %50:gpr32all = COPY %49.ssub
    $w0 = COPY %50
    RET_ReallyLR implicit $w0
...

# In this test case we don't perform the reassociation because we don't recognize the
# instruction at the top of the chain.
# CHECK-LABEL: name:  uabal_accumulation_with_different_start
# CHECK:          [[START1:%.*]]:fpr128 = ADDv4i32
# CHECK:          [[START2:%.*]]:fpr128 = UABDLv4i16_v4i32
# CHECK:          [[START3:%.*]]:fpr128 = UABDLv4i16_v4i32
# CHECK:          [[A1:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[START1]]
# CHECK:          [[B1:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[START2]]
# CHECK:          [[C1:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[START3]]
# CHECK:          [[A2:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[A1]]
# CHECK:          [[B2:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[B1]]
# CHECK:          [[C2:%.*]]:fpr128 = UABALv4i16_v4i32 killed [[C1]]
# CHECK:          [[PARTIAL_SUM:%.*]]:fpr128 = ADDv4i32 killed [[A2]], killed [[B2]]
# CHECK:          [[TOTAL_SUM:%.*]]:fpr128 = ADDv4i32 killed [[PARTIAL_SUM]], killed [[C2]]
# CHECK:          [[END:%.*]]:fpr32 = ADDVv4i32v killed [[TOTAL_SUM]]

---
name:            uabal_accumulation_with_different_start
body:             |
  bb.0.entry:
    liveins: $x0, $x1, $x2, $x3
  
    %3:gpr64 = COPY $x3
    %2:gpr64common = COPY $x2
    %1:gpr64 = COPY $x1
    %0:gpr64common = COPY $x0
    %4:fpr64 = LDRDui %0, 0 :: (load (s64))
    %5:fpr64 = LDRDui %2, 0 :: (load (s64))
    %6:gpr64common = ADDXrr %0, %1
    %7:gpr64common = ADDXrr %2, %3
    %8:fpr128 = LDRQui %6, 0 :: (load (s128))
    %9:fpr128 = LDRQui %7, 0 :: (load (s128))
    %10:fpr128 = ADDv4i32 killed %8, killed %9
    %11:fpr128 = UABALv4i16_v4i32 killed %10, killed %4, killed %5
    %12:gpr64common = ADDXrr %6, %1
    %13:gpr64common = ADDXrr %7, %3
    %14:fpr64 = LDRDui %12, 0 :: (load (s64))
    %15:fpr64 = LDRDui %13, 0 :: (load (s64))
    %16:fpr128 = UABALv4i16_v4i32 killed %11, killed %14, killed %15
    %17:gpr64common = ADDXrr %12, %1
    %18:gpr64common = ADDXrr %13, %3
    %19:fpr64 = LDRDui %17, 0 :: (load (s64))
    %20:fpr64 = LDRDui %18, 0 :: (load (s64))
    %21:fpr128 = UABALv4i16_v4i32 killed %16, killed %19, killed %20
    %22:gpr64common = ADDXrr %17, %1
    %23:gpr64common = ADDXrr %18, %3
    %24:fpr64 = LDRDui %22, 0 :: (load (s64))
    %25:fpr64 = LDRDui %23, 0 :: (load (s64))
    %26:fpr128 = UABALv4i16_v4i32 killed %21, killed %24, killed %25
    %27:gpr64common = ADDXrr %22, %1
    %28:gpr64common = ADDXrr %23, %3
    %29:fpr64 = LDRDui %27, 0 :: (load (s64))
    %30:fpr64 = LDRDui %28, 0 :: (load (s64))
    %31:fpr128 = UABALv4i16_v4i32 killed %26, killed %29, killed %30
    %32:gpr64common = ADDXrr %27, %1
    %33:gpr64common = ADDXrr %28, %3
    %34:fpr64 = LDRDui %32, 0 :: (load (s64))
    %35:fpr64 = LDRDui %33, 0 :: (load (s64))
    %36:fpr128 = UABALv4i16_v4i32 killed %31, killed %34, killed %35
    %37:gpr64common = ADDXrr %32, %1
    %38:gpr64common = ADDXrr %33, %3
    %39:fpr64 = LDRDui %37, 0 :: (load (s64))
    %40:fpr64 = LDRDui %38, 0 :: (load (s64))
    %41:fpr128 = UABALv4i16_v4i32 killed %36, killed %39, killed %40
    %42:gpr64common = ADDXrr %37, %1
    %43:gpr64common = ADDXrr %38, %3
    %44:fpr64 = LDRDui %42, 0 :: (load (s64))
    %45:fpr64 = LDRDui %43, 0 :: (load (s64))
    %46:fpr128 = UABALv4i16_v4i32 killed %41, killed %44, killed %45
    %47:fpr32 = ADDVv4i32v killed %46
    %48:fpr128 = IMPLICIT_DEF
    %49:fpr128 = INSERT_SUBREG %48, killed %47, %subreg.ssub
    %50:gpr32all = COPY %49.ssub
    $w0 = COPY %50
    RET_ReallyLR implicit $w0

...