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|
# RUN: llc -mtriple=amdgcn-- -mcpu=gfx900 -run-pass=print-machine-uniformity -o - %s 2>&1 | FileCheck %s
# loads from flat non uniform
---
name: flatloads
tracksRegLiveness: true
machineFunctionInfo:
isEntryFunction: true
body: |
bb.0:
; CHECK-LABEL: MachineUniformityInfo for function: flatloads
; CHECK: DIVERGENT: %1
; CHECK-NOT: DIVERGENT: %2
%0:vreg_64 = IMPLICIT_DEF
%1:vgpr_32(s32) = FLAT_LOAD_DWORD %0, 0, 0, implicit $exec, implicit $flat_scr :: (load (s32))
%2:vgpr_32(s32) = FLAT_LOAD_DWORD %0, 0, 0, implicit $exec, implicit $flat_scr :: (load (s32), addrspace 1)
%3:sreg_32 = V_READFIRSTLANE_B32 %1(s32), implicit $exec
S_ENDPGM 0
...
# loads from scratch non uniform
---
name: scratchloads
tracksRegLiveness: true
machineFunctionInfo:
isEntryFunction: true
body: |
bb.0:
; CHECK-LABEL: MachineUniformityInfo for function: scratchloads
; CHECK: DIVERGENT: %1
%0:vgpr_32 = V_MOV_B32_e32 0, implicit $exec
%1:vgpr_32 = SCRATCH_LOAD_DWORD %0, 0, 0, implicit $exec, implicit $flat_scr :: (load (s32), addrspace 5)
S_ENDPGM 0
...
# Global load
---
name: globalloads
tracksRegLiveness: true
machineFunctionInfo:
isEntryFunction: true
body: |
bb.0:
; CHECK-LABEL: MachineUniformityInfo for function: globalloads
; CHECK: DIVERGENT: %2
; CHECK-NOT: DIVERGENT: %3
%0:vreg_64 = IMPLICIT_DEF
%1:vreg_64 = IMPLICIT_DEF
%2:vgpr_32(s32) = GLOBAL_LOAD_DWORD %0, 0, 0, implicit $exec, implicit $flat_scr :: (load (s32))
%3:vreg_64 = GLOBAL_LOAD_DWORDX2 %1, 0, 0, implicit $exec :: (load (s64), addrspace 1)
%4:sreg_32 = V_READFIRSTLANE_B32 %2(s32), implicit $exec
S_ENDPGM 0
...
# FIXME:: ADDTID might instruction incorrectly marked uniform
---
name: dsreads
tracksRegLiveness: true
machineFunctionInfo:
isEntryFunction: true
body: |
bb.0:
; CHECK-LABEL: MachineUniformityInfo for function: dsreads
; CHECK-NEXT: ALL VALUES UNIFORM
%0:vreg_64 = IMPLICIT_DEF
$m0 = S_MOV_B32 0
%1:vgpr_32 = DS_READ_ADDTID_B32 0, 0, implicit $m0, implicit $exec
S_ENDPGM 0
...
# copy source == $sgpr => uniform, $vgpr => divergent
---
name: sgprcopy
tracksRegLiveness: true
machineFunctionInfo:
isEntryFunction: true
body: |
bb.0:
; CHECK-LABEL: MachineUniformityInfo for function: sgprcopy
; CHECK: DIVERGENT: %2
liveins: $sgpr0,$sgpr1,$vgpr0
%0:sgpr_32 = COPY $sgpr0
%1:vgpr_32 = COPY $sgpr1
%2:vgpr_32 = COPY $vgpr0
S_ENDPGM 0
...
# writelane is not uniform
---
name: writelane
machineFunctionInfo:
isEntryFunction: true
body: |
bb.0:
; CHECK-LABEL: MachineUniformityInfo for function: writelane
; CHECK: DIVERGENT: %4
; Note how %5 is the result of a vector compare, but it is reported as
; uniform because it is stored in an sreg.
; CHECK-NOT: DIVERGENT: %5
%0:vgpr_32 = IMPLICIT_DEF
%1:vgpr_32 = IMPLICIT_DEF
%2:sgpr_32 = V_READFIRSTLANE_B32 %0, implicit $exec
%3:sgpr_32 = V_READLANE_B32 %1, 0, implicit $exec
$sgpr0 = V_READFIRSTLANE_B32 $vgpr0, implicit $exec
$sgpr1 = V_READLANE_B32 $vgpr1, $sgpr0, implicit $exec
%4:vgpr_32 = V_WRITELANE_B32 0, 0, %0, implicit $exec
%5:sreg_64 = V_CMP_EQ_U32_e64 %0, %4, implicit $exec
S_CBRANCH_VCCZ %bb.1, implicit $vcc
bb.1:
%16:vgpr_32 = IMPLICIT_DEF
S_ENDPGM 0
...
# Directly reading physical vgpr not uniform
---
name: physicalreg
tracksRegLiveness: true
body: |
bb.0:
; CHECK-LABEL: MachineUniformityInfo for function: physicalreg
; CHECK: DIVERGENT: %0
; CHECK: DIVERGENT: %1
; CHECK: DIVERGENT: %2
; CHECK: DIVERGENT: %3
; CHECK: DIVERGENT: %4
; CHECK-NOT: DIVERGENT
; CHECK: DIVERGENT: %5
liveins: $vgpr0, $vgpr1, $vgpr2, $vgpr3, $vgpr4, $vgpr5
%0:vgpr_32 = COPY $vgpr0
%1:vgpr_32 = COPY $vgpr1
%2:vgpr_32 = V_AND_B32_e32 %1, $vgpr3, implicit $exec
%3:vgpr_32 = V_ADD_U32_e32 $vgpr2, $vgpr3, implicit $exec
%4:vgpr_32 = V_SUB_CO_U32_e32 $vgpr2, $vgpr3, implicit $exec, implicit-def $vcc
%5:vgpr_32 = V_AND_B32_e32 $vgpr4, $vgpr5, implicit $exec
S_ENDPGM 0
...
# mbcnt instructions are not uniform
---
name: mbcnt_lo
machineFunctionInfo:
isEntryFunction: true
body: |
bb.0:
; CHECK-LABEL: MachineUniformityInfo for function: mbcnt_lo
; CHECK: DIVERGENT: %0
%0:vgpr_32 = V_MBCNT_LO_U32_B32_e64 -1, 0, implicit $exec
S_ENDPGM 0
...
---
name: mbcnt_hi
machineFunctionInfo:
isEntryFunction: true
body: |
bb.0:
; CHECK-LABEL: MachineUniformityInfo for function: mbcnt_hi
; CHECK: DIVERGENT: %0
%0:vgpr_32 = V_MBCNT_HI_U32_B32_e64 -1, 0, implicit $exec
S_ENDPGM 0
...
|
