pr30821.mir 11.5 KB
# RUN: llc -x mir < %s -run-pass=greedy,virtregrewriter,stack-slot-coloring | FileCheck %s
--- |
  target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
  target triple = "x86_64-unknown-linux-gnu"

  define dso_local i32 @main() local_unnamed_addr {
  entry:
    ; Dummy IR that just performs some allocas -- the machine IR function
    ; below is what this test is about.
    %alpha = alloca i8, align 1
    %foxtrot = alloca <2 x double>, align 16
    %india = alloca <2 x double>, align 16
    ret i32 0
  }

...
---
name:            main
alignment:       16
exposesReturnsTwice: false
legalized:       false
regBankSelected: false
selected:        false
failedISel:      false
tracksRegLiveness: true
registers:
liveins:
frameInfo:
  isFrameAddressTaken: false
  isReturnAddressTaken: false
  hasStackMap:     false
  hasPatchPoint:   false
  stackSize:       0
  offsetAdjustment: 0
  maxAlignment:    16
  adjustsStack:    false
  hasCalls:        true
  stackProtector:  ''
  maxCallFrameSize: 4294967295
  hasOpaqueSPAdjustment: false
  hasVAStart:      false
  hasMustTailInVarArgFunc: false
  localFrameSize:  0
  savePoint:       ''
  restorePoint:    ''
fixedStack:
stack:
  - { id: 0, name: alpha, type: default, offset: 0, size: 1, alignment: 1,
      stack-id: default, callee-saved-register: '', callee-saved-restored: true,
      debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
  - { id: 1, name: foxtrot, type: default, offset: 0, size: 16, alignment: 16,
      stack-id: default, callee-saved-register: '', callee-saved-restored: true,
      debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
  - { id: 2, name: india, type: default, offset: 0, size: 16, alignment: 16,
      stack-id: default, callee-saved-register: '', callee-saved-restored: true,
      debug-info-variable: '', debug-info-expression: '',
      debug-info-location: '' }
constants:
body:             |
  bb.0.entry:
    ; To trick stack-slot-colouring to run its dead-store-elimination phase,
    ; which is at fault, we need the register allocator to run, and spill in two
    ; places that can have their slots merged. Achieve this by volatile-loading
    ; data into $xmm[0-14] and volatile storing them later, leaving regalloc only
    ; $xmm15 to play with in the middle.
    ; Then, perform two virtreg load-and-store pairs, with the faulty code
    ; sequence in the middle (MOVSDrm then MOVAPDmr on the same slot). The 
    ; virtreg gets spilt; the corresponding stack slots merged; and faulty code
    ; sequence eliminated if LLVM is broken.

    ; Make first 15 $xmm registers live
    $xmm0 = MOVUPDrm %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 16 from %ir.india)
    $xmm1 = MOVUPDrm %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 16 from %ir.india)
    $xmm2 = MOVUPDrm %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 16 from %ir.india)
    $xmm3 = MOVUPDrm %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 16 from %ir.india)
    $xmm4 = MOVUPDrm %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 16 from %ir.india)
    $xmm5 = MOVUPDrm %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 16 from %ir.india)
    $xmm6 = MOVUPDrm %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 16 from %ir.india)
    $xmm7 = MOVUPDrm %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 16 from %ir.india)
    $xmm8 = MOVUPDrm %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 16 from %ir.india)
    $xmm9 = MOVUPDrm %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 16 from %ir.india)
    $xmm10 = MOVUPDrm %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 16 from %ir.india)
    $xmm11 = MOVUPDrm %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 16 from %ir.india)
    $xmm12 = MOVUPDrm %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 16 from %ir.india)
    $xmm13 = MOVUPDrm %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 16 from %ir.india)
    $xmm14 = MOVUPDrm %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 16 from %ir.india)

    ; First vreg load
    %1:vr128 = MOVUPDrm %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 16 from %ir.india)

    ; First faulty sequence; %1 spilt
    %12:fr64 = MOVSDrm_alt %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 8 from %ir.india)
    %13:vr128 = COPY killed %12
    MOVAPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed %13 :: (volatile store 16 into %ir.india)
    ; CHECK: renamable $xmm{{[0-9]+}} = MOVSDrm_alt %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 8 from %ir.india)
    ; CHECK-NEXT: MOVAPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed renamable $xmm{{[0-9]+}} :: (volatile store 16 into %ir.india)

    ; Store %1 to avoid it being optimised out, will result in a load-from-spill
    MOVUPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed %1 :: (volatile dereferenceable store 16 into %ir.india)

    ; That code sequence a second time, to generate a second spill slot that
    ; will get coloured and merged.
    %2:vr128 = MOVUPDrm %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 16 from %ir.india)

    %22:fr64 = MOVSDrm_alt %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 8 from %ir.india)
    %23:vr128 = COPY killed %22
    MOVAPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed %23 :: (volatile store 16 into %ir.india)

    ; CHECK: renamable $xmm{{[0-9]+}} = MOVSDrm_alt %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 8 from %ir.india)
    ; CHECK-NEXT: MOVAPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed renamable $xmm{{[0-9]+}} :: (volatile store 16 into %ir.india)

    MOVUPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed %2 :: (volatile dereferenceable store 16 into %ir.india)


    ; Test some sequences that _should_ be eliminated
    %3:vr128 = MOVUPDrm %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 16 from %ir.india)

    %32:fr64 = VMOVSDrm_alt %stack.2.india, 1, $noreg, 0, $noreg :: (dereferenceable load 8 from %ir.india)
    %33:fr64 = COPY killed %32
    VMOVSDmr %stack.2.india, 1, $noreg, 0, $noreg, killed %33 :: (store 8 into %ir.india)

    ; This is the spill introduced by regalloc; we check that the inner dead
    ; store and load were eliminated
    ; CHECK: MOVAPSmr %stack.3, 1, $noreg, 0, $noreg, killed renamable $xmm{{[0-9]+}} :: (store 16 into %stack.3)
    ; CHECK-NEXT:renamable $xmm{{[0-9]+}} = MOVAPSrm %stack.3, 1, $noreg, 0, $noreg :: (load 16 from %stack.3)

    MOVUPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed %3 :: (volatile dereferenceable store 16 into %ir.india)


    ; Moves with different encodings but same size should be eliminated
    %4:vr128 = MOVUPDrm %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 16 from %ir.india)

    %42:fr32 = MOVSSrm_alt %stack.2.india, 1, $noreg, 0, $noreg :: (dereferenceable load 4 from %ir.india)
    %43:fr32 = COPY killed %42
    VMOVSSZmr %stack.2.india, 1, $noreg, 0, $noreg, killed %43 :: (store 4 into %ir.india)

    ; CHECK: MOVAPSmr %stack.3, 1, $noreg, 0, $noreg, killed renamable $xmm{{[0-9]+}} :: (store 16 into %stack.3)
    ; CHECK-NEXT:renamable $xmm{{[0-9]+}} = MOVAPSrm %stack.3, 1, $noreg, 0, $noreg :: (load 16 from %stack.3)

    MOVUPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed %4 :: (volatile dereferenceable store 16 into %ir.india)


    ; Same deal with double-size
    %5:vr128 = MOVUPDrm %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 16 from %ir.india)

    %52:fr64 = MOVSDrm_alt %stack.2.india, 1, $noreg, 0, $noreg :: (dereferenceable load 8 from %ir.india)
    %53:fr64 = COPY killed %52
    VMOVSDZmr %stack.2.india, 1, $noreg, 0, $noreg, killed %53 :: (store 8 into %ir.india)

    ; CHECK: MOVAPSmr %stack.3, 1, $noreg, 0, $noreg, killed renamable $xmm{{[0-9]+}} :: (store 16 into %stack.3)
    ; CHECK-NEXT:renamable $xmm{{[0-9]+}} = MOVAPSrm %stack.3, 1, $noreg, 0, $noreg :: (load 16 from %stack.3)

    MOVUPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed %5 :: (volatile dereferenceable store 16 into %ir.india)


    ; Last two repeated, with load/store opcode flipped
    %6:vr128 = MOVUPDrm %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 16 from %ir.india)

    %62:fr32 = VMOVSSZrm_alt %stack.2.india, 1, $noreg, 0, $noreg :: (dereferenceable load 4 from %ir.india)
    %63:fr32 = COPY killed %62
    MOVSSmr %stack.2.india, 1, $noreg, 0, $noreg, killed %63 :: (store 4 into %ir.india)

    ; CHECK: MOVAPSmr %stack.3, 1, $noreg, 0, $noreg, killed renamable $xmm{{[0-9]+}} :: (store 16 into %stack.3)
    ; CHECK-NEXT:renamable $xmm{{[0-9]+}} = MOVAPSrm %stack.3, 1, $noreg, 0, $noreg :: (load 16 from %stack.3)

    MOVUPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed %6 :: (volatile dereferenceable store 16 into %ir.india)


    ; Flipped double-size different-encoding test
    %7:vr128 = MOVUPDrm %stack.2.india, 1, $noreg, 0, $noreg :: (volatile dereferenceable load 16 from %ir.india)

    %72:fr64 = VMOVSDZrm_alt %stack.2.india, 1, $noreg, 0, $noreg :: (dereferenceable load 8 from %ir.india)
    %73:fr64 = COPY killed %72
    MOVSDmr %stack.2.india, 1, $noreg, 0, $noreg, killed %73 :: (store 8 into %ir.india)

    ; CHECK: MOVAPSmr %stack.3, 1, $noreg, 0, $noreg, killed renamable $xmm{{[0-9]+}} :: (store 16 into %stack.3)
    ; CHECK-NEXT:renamable $xmm{{[0-9]+}} = MOVAPSrm %stack.3, 1, $noreg, 0, $noreg :: (load 16 from %stack.3)

    MOVUPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed %7 :: (volatile dereferenceable store 16 into %ir.india)


    ; Stores of first 15 $xmm registers to keep them live across the middle of
    ; this bb.
    MOVUPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed $xmm0 :: (volatile dereferenceable store 16 into %ir.india)
    MOVUPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed $xmm1 :: (volatile dereferenceable store 16 into %ir.india)
    MOVUPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed $xmm2 :: (volatile dereferenceable store 16 into %ir.india)
    MOVUPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed $xmm3 :: (volatile dereferenceable store 16 into %ir.india)
    MOVUPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed $xmm4 :: (volatile dereferenceable store 16 into %ir.india)
    MOVUPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed $xmm5 :: (volatile dereferenceable store 16 into %ir.india)
    MOVUPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed $xmm6 :: (volatile dereferenceable store 16 into %ir.india)
    MOVUPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed $xmm7 :: (volatile dereferenceable store 16 into %ir.india)
    MOVUPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed $xmm8 :: (volatile dereferenceable store 16 into %ir.india)
    MOVUPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed $xmm9 :: (volatile dereferenceable store 16 into %ir.india)
    MOVUPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed $xmm10 :: (volatile dereferenceable store 16 into %ir.india)
    MOVUPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed $xmm11 :: (volatile dereferenceable store 16 into %ir.india)
    MOVUPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed $xmm12 :: (volatile dereferenceable store 16 into %ir.india)
    MOVUPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed $xmm13 :: (volatile dereferenceable store 16 into %ir.india)
    MOVUPDmr %stack.2.india, 1, $noreg, 0, $noreg, killed $xmm14 :: (volatile dereferenceable store 16 into %ir.india)

    RET 0

...