1
0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-11-22 18:54:02 +01:00
llvm-mirror/test/CodeGen/AMDGPU/array-ptr-calc-i32.ll
Scott Linder a70016c8d5 [AMDGPU] Add Scratch Wave Offset to Scratch Buffer Descriptor in entry functions
Add the scratch wave offset to the scratch buffer descriptor (SRSrc) in
the entry function prologue. This allows us to removes the scratch wave
offset register from the calling convention ABI.

As part of this change, allow the use of an inline constant zero for the
SOffset of MUBUF instructions accessing the stack in entry functions
when a frame pointer is not requested/required. Entry functions with
calls still need to set up the calling convention ABI stack pointer
register, and reference it in order to address arguments of called
functions. The ABI stack pointer register remains unswizzled, but is now
wave-relative instead of queue-relative.

Non-entry functions also use an inline constant zero SOffset for
wave-relative scratch access, but continue to use the stack and frame
pointers as before. When the stack or frame pointer is converted to a
swizzled offset it is now scaled directly, as the scratch wave offset no
longer needs to be subtracted first.

Update llvm/docs/AMDGPUUsage.rst to reflect these changes to the calling
convention.

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D75138
2020-03-19 15:35:16 -04:00

51 lines
2.5 KiB
LLVM

; RUN: llc -verify-machineinstrs -march=amdgcn -mcpu=tahiti -mattr=-promote-alloca < %s | FileCheck -check-prefix=SI-ALLOCA -check-prefix=SI %s
; RUN: llc -verify-machineinstrs -march=amdgcn -mcpu=tahiti -mattr=+promote-alloca < %s | FileCheck -check-prefix=SI-PROMOTE -check-prefix=SI %s
declare i32 @llvm.amdgcn.mbcnt.lo(i32, i32) #1
declare i32 @llvm.amdgcn.mbcnt.hi(i32, i32) #1
declare void @llvm.amdgcn.s.barrier() #2
; The required pointer calculations for the alloca'd actually requires
; an add and won't be folded into the addressing, which fails with a
; 64-bit pointer add. This should work since private pointers should
; be 32-bits.
; SI-LABEL: {{^}}test_private_array_ptr_calc:
; SI-ALLOCA: v_add_i32_e32 [[PTRREG:v[0-9]+]], vcc, 16, v{{[0-9]+}}
; SI-ALLOCA: buffer_store_dword {{v[0-9]+}}, [[PTRREG]], s[{{[0-9]+:[0-9]+}}], 0 offen offset:64
; SI-ALLOCA: s_barrier
; SI-ALLOCA: buffer_load_dword {{v[0-9]+}}, [[PTRREG]], s[{{[0-9]+:[0-9]+}}], 0 offen offset:64
;
; FIXME: The AMDGPUPromoteAlloca pass should be able to convert this
; alloca to a vector. It currently fails because it does not know how
; to interpret:
; getelementptr inbounds [16 x i32], [16 x i32] addrspace(5)* %alloca, i32 1, i32 %b
; SI-PROMOTE: v_add_i32_e32 [[PTRREG:v[0-9]+]], vcc, 64
; SI-PROMOTE: ds_write_b32 [[PTRREG]]
define amdgpu_kernel void @test_private_array_ptr_calc(i32 addrspace(1)* noalias %out, i32 addrspace(1)* noalias %inA, i32 addrspace(1)* noalias %inB) #0 {
%alloca = alloca [16 x i32], align 16, addrspace(5)
%mbcnt.lo = call i32 @llvm.amdgcn.mbcnt.lo(i32 -1, i32 0);
%tid = call i32 @llvm.amdgcn.mbcnt.hi(i32 -1, i32 %mbcnt.lo)
%a_ptr = getelementptr inbounds i32, i32 addrspace(1)* %inA, i32 %tid
%b_ptr = getelementptr inbounds i32, i32 addrspace(1)* %inB, i32 %tid
%a = load i32, i32 addrspace(1)* %a_ptr, !range !0
%b = load i32, i32 addrspace(1)* %b_ptr, !range !0
%result = add i32 %a, %b
%alloca_ptr = getelementptr inbounds [16 x i32], [16 x i32] addrspace(5)* %alloca, i32 1, i32 %b
store i32 %result, i32 addrspace(5)* %alloca_ptr, align 4
; Dummy call
call void @llvm.amdgcn.s.barrier()
%reload = load i32, i32 addrspace(5)* %alloca_ptr, align 4, !range !0
%out_ptr = getelementptr inbounds i32, i32 addrspace(1)* %out, i32 %tid
store i32 %reload, i32 addrspace(1)* %out_ptr, align 4
ret void
}
attributes #0 = { nounwind "amdgpu-waves-per-eu"="1,1" "amdgpu-flat-work-group-size"="1,256" }
attributes #1 = { nounwind readnone }
attributes #2 = { nounwind convergent }
!0 = !{i32 0, i32 65536 }