[llvm] r325518 - [AMDGPU] Increased vector length for global/constant loads.
Mark Searles via llvm-commits
llvm-commits at lists.llvm.org
Mon Feb 19 08:42:49 PST 2018
Author: msearles
Date: Mon Feb 19 08:42:49 2018
New Revision: 325518
URL: http://llvm.org/viewvc/llvm-project?rev=325518&view=rev
Log:
[AMDGPU] Increased vector length for global/constant loads.
Summary: GCN ISA supports instructions that can read 16 consecutive dwords from memory through the scalar data cache; loadstoreVectorizer should take advantage of the wider vector length and pack 16/8 elements of dwords/quadwords.
Author: FarhanaAleen
Reviewed By: rampitec
Subscribers: llvm-commits, AMDGPU
Differential Revision: https://reviews.llvm.org/D43275
Added:
llvm/trunk/test/CodeGen/AMDGPU/load-constant-f32.ll
Modified:
llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.cpp
llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.h
llvm/trunk/test/CodeGen/AMDGPU/load-constant-f64.ll
llvm/trunk/test/CodeGen/AMDGPU/waitcnt-looptest.ll
Modified: llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.cpp?rev=325518&r1=325517&r2=325518&view=diff
==============================================================================
--- llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.cpp (original)
+++ llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.cpp Mon Feb 19 08:42:49 2018
@@ -233,12 +233,38 @@ unsigned AMDGPUTTIImpl::getMinVectorRegi
return 32;
}
+unsigned AMDGPUTTIImpl::getLoadVectorFactor(unsigned VF, unsigned LoadSize,
+ unsigned ChainSizeInBytes,
+ VectorType *VecTy) const {
+ unsigned VecRegBitWidth = VF * LoadSize;
+ if (VecRegBitWidth > 128 && VecTy->getScalarSizeInBits() < 32)
+ // TODO: Support element-size less than 32bit?
+ return 128 / LoadSize;
+
+ return VF;
+}
+
+unsigned AMDGPUTTIImpl::getStoreVectorFactor(unsigned VF, unsigned StoreSize,
+ unsigned ChainSizeInBytes,
+ VectorType *VecTy) const {
+ unsigned VecRegBitWidth = VF * StoreSize;
+ if (VecRegBitWidth > 128)
+ return 128 / StoreSize;
+
+ return VF;
+}
+
unsigned AMDGPUTTIImpl::getLoadStoreVecRegBitWidth(unsigned AddrSpace) const {
AMDGPUAS AS = ST->getAMDGPUAS();
if (AddrSpace == AS.GLOBAL_ADDRESS ||
AddrSpace == AS.CONSTANT_ADDRESS ||
- AddrSpace == AS.CONSTANT_ADDRESS_32BIT ||
- AddrSpace == AS.FLAT_ADDRESS)
+ AddrSpace == AS.CONSTANT_ADDRESS_32BIT) {
+ if (ST->getGeneration() <= AMDGPUSubtarget::NORTHERN_ISLANDS)
+ return 128;
+ return 512;
+ }
+
+ if (AddrSpace == AS.FLAT_ADDRESS)
return 128;
if (AddrSpace == AS.LOCAL_ADDRESS ||
AddrSpace == AS.REGION_ADDRESS)
Modified: llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.h?rev=325518&r1=325517&r2=325518&view=diff
==============================================================================
--- llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.h (original)
+++ llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.h Mon Feb 19 08:42:49 2018
@@ -118,6 +118,12 @@ public:
unsigned getNumberOfRegisters(bool Vector) const;
unsigned getRegisterBitWidth(bool Vector) const;
unsigned getMinVectorRegisterBitWidth() const;
+ unsigned getLoadVectorFactor(unsigned VF, unsigned LoadSize,
+ unsigned ChainSizeInBytes,
+ VectorType *VecTy) const;
+ unsigned getStoreVectorFactor(unsigned VF, unsigned StoreSize,
+ unsigned ChainSizeInBytes,
+ VectorType *VecTy) const;
unsigned getLoadStoreVecRegBitWidth(unsigned AddrSpace) const;
bool isLegalToVectorizeMemChain(unsigned ChainSizeInBytes,
Added: llvm/trunk/test/CodeGen/AMDGPU/load-constant-f32.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/AMDGPU/load-constant-f32.ll?rev=325518&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/AMDGPU/load-constant-f32.ll (added)
+++ llvm/trunk/test/CodeGen/AMDGPU/load-constant-f32.ll Mon Feb 19 08:42:49 2018
@@ -0,0 +1,37 @@
+; RUN: llc -march=amdgcn -verify-machineinstrs < %s | FileCheck -check-prefix=GCN -check-prefix=FUNC %s
+; RUN: llc -march=r600 -mcpu=redwood < %s | FileCheck -check-prefix=EG -check-prefix=FUNC %s
+
+; Tests whether a load chain of 8 constants gets vectorized into a wider load.
+; FUNC-LABEL: {{^}}constant_load_v8f32:
+; GCN: s_load_dwordx8
+; EG: VTX_READ_128
+; EG: VTX_READ_128
+define amdgpu_kernel void @constant_load_v8f32(float addrspace(4)* noalias nocapture readonly %weights, float addrspace(1)* noalias nocapture %out_ptr) {
+entry:
+ %out_ptr.promoted = load float, float addrspace(1)* %out_ptr, align 4
+ %tmp = load float, float addrspace(4)* %weights, align 4
+ %add = fadd float %tmp, %out_ptr.promoted
+ %arrayidx.1 = getelementptr inbounds float, float addrspace(4)* %weights, i64 1
+ %tmp1 = load float, float addrspace(4)* %arrayidx.1, align 4
+ %add.1 = fadd float %tmp1, %add
+ %arrayidx.2 = getelementptr inbounds float, float addrspace(4)* %weights, i64 2
+ %tmp2 = load float, float addrspace(4)* %arrayidx.2, align 4
+ %add.2 = fadd float %tmp2, %add.1
+ %arrayidx.3 = getelementptr inbounds float, float addrspace(4)* %weights, i64 3
+ %tmp3 = load float, float addrspace(4)* %arrayidx.3, align 4
+ %add.3 = fadd float %tmp3, %add.2
+ %arrayidx.4 = getelementptr inbounds float, float addrspace(4)* %weights, i64 4
+ %tmp4 = load float, float addrspace(4)* %arrayidx.4, align 4
+ %add.4 = fadd float %tmp4, %add.3
+ %arrayidx.5 = getelementptr inbounds float, float addrspace(4)* %weights, i64 5
+ %tmp5 = load float, float addrspace(4)* %arrayidx.5, align 4
+ %add.5 = fadd float %tmp5, %add.4
+ %arrayidx.6 = getelementptr inbounds float, float addrspace(4)* %weights, i64 6
+ %tmp6 = load float, float addrspace(4)* %arrayidx.6, align 4
+ %add.6 = fadd float %tmp6, %add.5
+ %arrayidx.7 = getelementptr inbounds float, float addrspace(4)* %weights, i64 7
+ %tmp7 = load float, float addrspace(4)* %arrayidx.7, align 4
+ %add.7 = fadd float %tmp7, %add.6
+ store float %add.7, float addrspace(1)* %out_ptr, align 4
+ ret void
+}
Modified: llvm/trunk/test/CodeGen/AMDGPU/load-constant-f64.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/AMDGPU/load-constant-f64.ll?rev=325518&r1=325517&r2=325518&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/AMDGPU/load-constant-f64.ll (original)
+++ llvm/trunk/test/CodeGen/AMDGPU/load-constant-f64.ll Mon Feb 19 08:42:49 2018
@@ -13,3 +13,36 @@ define amdgpu_kernel void @constant_load
}
attributes #0 = { nounwind }
+
+; Tests whether a load-chain of 8 constants of 64bit each gets vectorized into a wider load.
+; FUNC-LABEL: {{^}}constant_load_2v4f64:
+; GCN: s_load_dwordx16
+define amdgpu_kernel void @constant_load_2v4f64(double addrspace(4)* noalias nocapture readonly %weights, double addrspace(1)* noalias nocapture %out_ptr) {
+entry:
+ %out_ptr.promoted = load double, double addrspace(1)* %out_ptr, align 4
+ %tmp = load double, double addrspace(4)* %weights, align 4
+ %add = fadd double %tmp, %out_ptr.promoted
+ %arrayidx.1 = getelementptr inbounds double, double addrspace(4)* %weights, i64 1
+ %tmp1 = load double, double addrspace(4)* %arrayidx.1, align 4
+ %add.1 = fadd double %tmp1, %add
+ %arrayidx.2 = getelementptr inbounds double, double addrspace(4)* %weights, i64 2
+ %tmp2 = load double, double addrspace(4)* %arrayidx.2, align 4
+ %add.2 = fadd double %tmp2, %add.1
+ %arrayidx.3 = getelementptr inbounds double, double addrspace(4)* %weights, i64 3
+ %tmp3 = load double, double addrspace(4)* %arrayidx.3, align 4
+ %add.3 = fadd double %tmp3, %add.2
+ %arrayidx.4 = getelementptr inbounds double, double addrspace(4)* %weights, i64 4
+ %tmp4 = load double, double addrspace(4)* %arrayidx.4, align 4
+ %add.4 = fadd double %tmp4, %add.3
+ %arrayidx.5 = getelementptr inbounds double, double addrspace(4)* %weights, i64 5
+ %tmp5 = load double, double addrspace(4)* %arrayidx.5, align 4
+ %add.5 = fadd double %tmp5, %add.4
+ %arrayidx.6 = getelementptr inbounds double, double addrspace(4)* %weights, i64 6
+ %tmp6 = load double, double addrspace(4)* %arrayidx.6, align 4
+ %add.6 = fadd double %tmp6, %add.5
+ %arrayidx.7 = getelementptr inbounds double, double addrspace(4)* %weights, i64 7
+ %tmp7 = load double, double addrspace(4)* %arrayidx.7, align 4
+ %add.7 = fadd double %tmp7, %add.6
+ store double %add.7, double addrspace(1)* %out_ptr, align 4
+ ret void
+}
Modified: llvm/trunk/test/CodeGen/AMDGPU/waitcnt-looptest.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/AMDGPU/waitcnt-looptest.ll?rev=325518&r1=325517&r2=325518&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/AMDGPU/waitcnt-looptest.ll (original)
+++ llvm/trunk/test/CodeGen/AMDGPU/waitcnt-looptest.ll Mon Feb 19 08:42:49 2018
@@ -1,4 +1,4 @@
-; RUN: llc < %s -mtriple=amdgcn--amdhsa -mcpu=fiji -mattr=-flat-for-global | FileCheck --check-prefix=GCN %s
+; RUN: llc < %s -mtriple=amdgcn--amdhsa -mcpu=fiji -mattr=-flat-for-global -amdgpu-load-store-vectorizer=0 | FileCheck --check-prefix=GCN %s
; Check that the waitcnt insertion algorithm correctly propagates wait counts
; from before a loop to the loop header.
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