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/llvm.amdgcn.buffer.atomic.ll
Neil Henning 914315597c [AMDGPU] Add an AMDGPU specific atomic optimizer.
This commit adds a new IR level pass to the AMDGPU backend to perform
atomic optimizations. It works by:

- Running through a function and finding atomicrmw add/sub or uses of
  the atomic buffer intrinsics for add/sub.
- If all arguments except the value to be added/subtracted are uniform,
  record the value to be optimized.
- Run through the atomic operations we can optimize and, depending on
  whether the value is uniform/divergent use wavefront wide operations
  (DPP in the divergent case) to calculate the total amount to be
  atomically added/subtracted.
- Then let only a single lane of each wavefront perform the atomic
  operation, reducing the total number of atomic operations in flight.
- Lastly we recombine the result from the single lane to each lane of
  the wavefront, and calculate our individual lanes offset into the
  final result.

Differential Revision: https://reviews.llvm.org/D51969

llvm-svn: 343973
2018-10-08 15:49:19 +00:00

130 lines
7.0 KiB
LLVM

;RUN: llc < %s -march=amdgcn -mcpu=verde -amdgpu-atomic-optimizations=false -verify-machineinstrs | FileCheck %s -check-prefix=CHECK -check-prefix=SICI
;RUN: llc < %s -march=amdgcn -mcpu=tonga -amdgpu-atomic-optimizations=false -verify-machineinstrs | FileCheck %s -check-prefix=CHECK -check-prefix=VI
;CHECK-LABEL: {{^}}test1:
;CHECK-NOT: s_waitcnt
;CHECK: buffer_atomic_swap v0, off, s[0:3], 0 glc
;VI: s_movk_i32 [[SOFS:s[0-9]+]], 0x1ffc
;CHECK: s_waitcnt vmcnt(0)
;CHECK: buffer_atomic_swap v0, v1, s[0:3], 0 idxen glc
;CHECK: s_waitcnt vmcnt(0)
;CHECK: buffer_atomic_swap v0, v2, s[0:3], 0 offen glc
;CHECK: s_waitcnt vmcnt(0)
;CHECK: buffer_atomic_swap v0, v[1:2], s[0:3], 0 idxen offen glc
;CHECK: s_waitcnt vmcnt(0)
;CHECK: buffer_atomic_swap v0, v2, s[0:3], 0 offen offset:42 glc
;CHECK-DAG: s_waitcnt vmcnt(0)
;SICI: buffer_atomic_swap v0, v1, s[0:3], 0 offen glc
;VI: buffer_atomic_swap v0, off, s[0:3], [[SOFS]] offset:4 glc
;CHECK: s_waitcnt vmcnt(0)
;CHECK: buffer_atomic_swap v0, off, s[0:3], 0{{$}}
define amdgpu_ps float @test1(<4 x i32> inreg %rsrc, i32 %data, i32 %vindex, i32 %voffset) {
main_body:
%o1 = call i32 @llvm.amdgcn.buffer.atomic.swap(i32 %data, <4 x i32> %rsrc, i32 0, i32 0, i1 0)
%o2 = call i32 @llvm.amdgcn.buffer.atomic.swap(i32 %o1, <4 x i32> %rsrc, i32 %vindex, i32 0, i1 0)
%o3 = call i32 @llvm.amdgcn.buffer.atomic.swap(i32 %o2, <4 x i32> %rsrc, i32 0, i32 %voffset, i1 0)
%o4 = call i32 @llvm.amdgcn.buffer.atomic.swap(i32 %o3, <4 x i32> %rsrc, i32 %vindex, i32 %voffset, i1 0)
%ofs.5 = add i32 %voffset, 42
%o5 = call i32 @llvm.amdgcn.buffer.atomic.swap(i32 %o4, <4 x i32> %rsrc, i32 0, i32 %ofs.5, i1 0)
%o6 = call i32 @llvm.amdgcn.buffer.atomic.swap(i32 %o5, <4 x i32> %rsrc, i32 0, i32 8192, i1 0)
%unused = call i32 @llvm.amdgcn.buffer.atomic.swap(i32 %o6, <4 x i32> %rsrc, i32 0, i32 0, i1 0)
%out = bitcast i32 %o6 to float
ret float %out
}
;CHECK-LABEL: {{^}}test2:
;CHECK-NOT: s_waitcnt
;CHECK: buffer_atomic_add v0, v1, s[0:3], 0 idxen glc
;CHECK: s_waitcnt vmcnt(0)
;CHECK: buffer_atomic_sub v0, v1, s[0:3], 0 idxen glc
;CHECK: s_waitcnt vmcnt(0)
;CHECK: buffer_atomic_smin v0, v1, s[0:3], 0 idxen glc
;CHECK: s_waitcnt vmcnt(0)
;CHECK: buffer_atomic_umin v0, v1, s[0:3], 0 idxen glc
;CHECK: s_waitcnt vmcnt(0)
;CHECK: buffer_atomic_smax v0, v1, s[0:3], 0 idxen glc
;CHECK: s_waitcnt vmcnt(0)
;CHECK: buffer_atomic_umax v0, v1, s[0:3], 0 idxen glc
;CHECK: s_waitcnt vmcnt(0)
;CHECK: buffer_atomic_and v0, v1, s[0:3], 0 idxen glc
;CHECK: s_waitcnt vmcnt(0)
;CHECK: buffer_atomic_or v0, v1, s[0:3], 0 idxen glc
;CHECK: s_waitcnt vmcnt(0)
;CHECK: buffer_atomic_xor v0, v1, s[0:3], 0 idxen glc
define amdgpu_ps float @test2(<4 x i32> inreg %rsrc, i32 %data, i32 %vindex) {
main_body:
%t1 = call i32 @llvm.amdgcn.buffer.atomic.add(i32 %data, <4 x i32> %rsrc, i32 %vindex, i32 0, i1 0)
%t2 = call i32 @llvm.amdgcn.buffer.atomic.sub(i32 %t1, <4 x i32> %rsrc, i32 %vindex, i32 0, i1 0)
%t3 = call i32 @llvm.amdgcn.buffer.atomic.smin(i32 %t2, <4 x i32> %rsrc, i32 %vindex, i32 0, i1 0)
%t4 = call i32 @llvm.amdgcn.buffer.atomic.umin(i32 %t3, <4 x i32> %rsrc, i32 %vindex, i32 0, i1 0)
%t5 = call i32 @llvm.amdgcn.buffer.atomic.smax(i32 %t4, <4 x i32> %rsrc, i32 %vindex, i32 0, i1 0)
%t6 = call i32 @llvm.amdgcn.buffer.atomic.umax(i32 %t5, <4 x i32> %rsrc, i32 %vindex, i32 0, i1 0)
%t7 = call i32 @llvm.amdgcn.buffer.atomic.and(i32 %t6, <4 x i32> %rsrc, i32 %vindex, i32 0, i1 0)
%t8 = call i32 @llvm.amdgcn.buffer.atomic.or(i32 %t7, <4 x i32> %rsrc, i32 %vindex, i32 0, i1 0)
%t9 = call i32 @llvm.amdgcn.buffer.atomic.xor(i32 %t8, <4 x i32> %rsrc, i32 %vindex, i32 0, i1 0)
%out = bitcast i32 %t9 to float
ret float %out
}
; Ideally, we would teach tablegen & friends that cmpswap only modifies the
; first vgpr. Since we don't do that yet, the register allocator will have to
; create copies which we don't bother to track here.
;
;CHECK-LABEL: {{^}}test3:
;CHECK-NOT: s_waitcnt
;CHECK: buffer_atomic_cmpswap {{v\[[0-9]+:[0-9]+\]}}, off, s[0:3], 0 glc
;CHECK: s_waitcnt vmcnt(0)
;VI: s_movk_i32 [[SOFS:s[0-9]+]], 0x1ffc
;CHECK: buffer_atomic_cmpswap {{v\[[0-9]+:[0-9]+\]}}, v2, s[0:3], 0 idxen glc
;CHECK: s_waitcnt vmcnt(0)
;CHECK: buffer_atomic_cmpswap {{v\[[0-9]+:[0-9]+\]}}, v3, s[0:3], 0 offen glc
;CHECK: s_waitcnt vmcnt(0)
;CHECK: buffer_atomic_cmpswap {{v\[[0-9]+:[0-9]+\]}}, v[2:3], s[0:3], 0 idxen offen glc
;CHECK: s_waitcnt vmcnt(0)
;CHECK: buffer_atomic_cmpswap {{v\[[0-9]+:[0-9]+\]}}, v3, s[0:3], 0 offen offset:44 glc
;CHECK-DAG: s_waitcnt vmcnt(0)
;SICI: buffer_atomic_cmpswap {{v\[[0-9]+:[0-9]+\]}}, {{v[0-9]+}}, s[0:3], 0 offen glc
;VI: buffer_atomic_cmpswap {{v\[[0-9]+:[0-9]+\]}}, off, s[0:3], [[SOFS]] offset:4 glc
define amdgpu_ps float @test3(<4 x i32> inreg %rsrc, i32 %data, i32 %cmp, i32 %vindex, i32 %voffset) {
main_body:
%o1 = call i32 @llvm.amdgcn.buffer.atomic.cmpswap(i32 %data, i32 %cmp, <4 x i32> %rsrc, i32 0, i32 0, i1 0)
%o2 = call i32 @llvm.amdgcn.buffer.atomic.cmpswap(i32 %o1, i32 %cmp, <4 x i32> %rsrc, i32 %vindex, i32 0, i1 0)
%o3 = call i32 @llvm.amdgcn.buffer.atomic.cmpswap(i32 %o2, i32 %cmp, <4 x i32> %rsrc, i32 0, i32 %voffset, i1 0)
%o4 = call i32 @llvm.amdgcn.buffer.atomic.cmpswap(i32 %o3, i32 %cmp, <4 x i32> %rsrc, i32 %vindex, i32 %voffset, i1 0)
%ofs.5 = add i32 %voffset, 44
%o5 = call i32 @llvm.amdgcn.buffer.atomic.cmpswap(i32 %o4, i32 %cmp, <4 x i32> %rsrc, i32 0, i32 %ofs.5, i1 0)
%o6 = call i32 @llvm.amdgcn.buffer.atomic.cmpswap(i32 %o5, i32 %cmp, <4 x i32> %rsrc, i32 0, i32 8192, i1 0)
; Detecting the no-return variant doesn't work right now because of how the
; intrinsic is replaced by an instruction that feeds into an EXTRACT_SUBREG.
; Since there probably isn't a reasonable use-case of cmpswap that discards
; the return value, that seems okay.
;
; %unused = call i32 @llvm.amdgcn.buffer.atomic.cmpswap(i32 %o6, i32 %cmp, <4 x i32> %rsrc, i32 0, i32 0, i1 0)
%out = bitcast i32 %o6 to float
ret float %out
}
;CHECK-LABEL: {{^}}test4:
;CHECK: buffer_atomic_add v0,
define amdgpu_ps float @test4() {
main_body:
%v = call i32 @llvm.amdgcn.buffer.atomic.add(i32 1, <4 x i32> undef, i32 0, i32 4, i1 false)
%v.float = bitcast i32 %v to float
ret float %v.float
}
declare i32 @llvm.amdgcn.buffer.atomic.swap(i32, <4 x i32>, i32, i32, i1) #0
declare i32 @llvm.amdgcn.buffer.atomic.add(i32, <4 x i32>, i32, i32, i1) #0
declare i32 @llvm.amdgcn.buffer.atomic.sub(i32, <4 x i32>, i32, i32, i1) #0
declare i32 @llvm.amdgcn.buffer.atomic.smin(i32, <4 x i32>, i32, i32, i1) #0
declare i32 @llvm.amdgcn.buffer.atomic.umin(i32, <4 x i32>, i32, i32, i1) #0
declare i32 @llvm.amdgcn.buffer.atomic.smax(i32, <4 x i32>, i32, i32, i1) #0
declare i32 @llvm.amdgcn.buffer.atomic.umax(i32, <4 x i32>, i32, i32, i1) #0
declare i32 @llvm.amdgcn.buffer.atomic.and(i32, <4 x i32>, i32, i32, i1) #0
declare i32 @llvm.amdgcn.buffer.atomic.or(i32, <4 x i32>, i32, i32, i1) #0
declare i32 @llvm.amdgcn.buffer.atomic.xor(i32, <4 x i32>, i32, i32, i1) #0
declare i32 @llvm.amdgcn.buffer.atomic.cmpswap(i32, i32, <4 x i32>, i32, i32, i1) #0
attributes #0 = { nounwind }