[AMDGPU] Propagate LDS align into to instructions

[arsenm]

llvm/lib/Target/AMDGPU/AMDGPULowerModuleLDSPass.cpp

339

This looks like you are reinventing getOrEnforceKnownAlignment

[arsenm]

llvm/lib/Target/AMDGPU/AMDGPULowerModuleLDSPass.cpp

339

I'm not sure why you need to do this. SelectionDAG does already try to increase the alignment after this point

[rampitec]

llvm/lib/Target/AMDGPU/AMDGPULowerModuleLDSPass.cpp

339

This looks like you are reinventing getOrEnforceKnownAlignment

It is not the same. I do not need to enforce alignment on an Value itself but propagate it down to loads and stores. I did not find such helper.

339

I'm not sure why you need to do this. SelectionDAG does already try to increase the alignment after this point

It actually does not, at least not in this scenario. You may notice there are actual codegen changes. I was checking -print-after-all and alignment stays the same all the way past selection. Besides there is also global isel. I assume the earlier we get better alignment the better.

[rampitec]

llvm/lib/Target/AMDGPU/AMDGPULowerModuleLDSPass.cpp

339

I'm not sure why you need to do this. SelectionDAG does already try to increase the alignment after this point

It actually does not, at least not in this scenario. You may notice there are actual codegen changes. I was checking -print-after-all and alignment stays the same all the way past selection. Besides there is also global isel. I assume the earlier we get better alignment the better.

I have checked, SDag only calls refineAlignment when it folds a node or for a mem intrinsic, which does not happen with the tests I am using. I hit zero bps in refineAlignment.

[rampitec]

Fixed formatting.

[rampitec]

PSDB passed.

[rampitec]

Rebased.

[hsmhsm]

llvm/lib/Target/AMDGPU/AMDGPULowerModuleLDSPass.cpp

317

Did not understand the logic behind calling commonAlignment() here. I thought, alignment of GV and GEP are same, and we just need to propogate the alignment of GV? Because, we already have properly updated the alignment of GV?

367

In case of GEP instruction, I thought, we should be exploring the uses of GEP?

374

Same here, in case of bitcast instruction, I thought, we should be exploring uses of bitcast?

[rampitec]

llvm/lib/Target/AMDGPU/AMDGPULowerModuleLDSPass.cpp

317

Did not understand the logic behind calling commonAlignment() here. I thought, alignment of GV and GEP are same, and we just need to propogate the alignment of GV? Because, we already have properly updated the alignment of GV?

Assume struct:

{ i64 x 16, i32 }

Second field has align 4 and that is the alignment of GV and GEP. But given the structure layout we can tell that actual efective alignment is 8. That is what commonAlignment() call is about.

367

In case of GEP instruction, I thought, we should be exploring the uses of GEP?

Yes, this is recursive call to refineUsesAlignment() with GEP as a Ptr.

374

Same here, in case of bitcast instruction, I thought, we should be exploring uses of bitcast?

Same here, recursive call explores uses of a cast.

[rampitec]

Rebased.

[hsmhsm]

LGTM

[foad]

llvm/lib/Target/AMDGPU/AMDGPULowerModuleLDSPass.cpp

349

For StoreInst, AtomicRMWInst, AtomicCmpXchgInst and GetElementPtrInst you need to check that the use is actually the "address" operand of the instruction.

[foad]

llvm/lib/Target/AMDGPU/AMDGPULowerModuleLDSPass.cpp

343

Could early-out here if Align==1 to save a lot of unnecessary work.

349

Oh, I see you are already checking it for GetElementPtrInst.

[rampitec]

llvm/lib/Target/AMDGPU/AMDGPULowerModuleLDSPass.cpp

349

None of AtomicRMW operators can use pointers. AtomicCmpXchgInst can.Actually I cannot come up with a test for GEP too. I think it is only possible if we start to process ConstantExpr here which is not handled right now.

Anyway, D104796 addresses this and Align == 1 case.

llvm/lib/Target/AMDGPU/AMDGPULowerModuleLDSPass.cpp

for (size_t I = 0; I < LocalVars.size(); I++) {
         });
       } else {
         GV->replaceAllUsesWith(GEP);
       }
       if (GV->use_empty()) {
         UsedList.erase(GV);
         GV->eraseFromParent();
       }
+
+      uint64_t Off = DL.getStructLayout(LDSTy)->getElementOffset(I);
+      Align A = commonAlignment(MaxAlign, Off);
+      refineUsesAlignment(GEP, A, DL);
     }
 
     // Mark kernels with asm that reads the address of the allocated structure
     // This is not necessary for lowering. This lets other passes, specifically
     // PromoteAlloca, accurately calculate how much LDS will be used by the
     // kernel after lowering.
     if (!F) {
       IRBuilder<> Builder(Ctx);
       SmallPtrSet<Function *, 32> Kernels;
       for (auto &I : M.functions()) {
         Function *Func = &I;
         if (AMDGPU::isKernelCC(Func) && !Kernels.contains(Func)) {
           markUsedByKernel(Builder, Func, SGV);
           Kernels.insert(Func);
         }
       }
     }
     return true;
   }
+
+  void refineUsesAlignment(Value *Ptr, Align A, const DataLayout &DL,
+                           unsigned MaxDepth = 5) {
+    if (!MaxDepth)
+      return;
+
+    for (User *U : Ptr->users()) {
+      if (auto *LI = dyn_cast<LoadInst>(U)) {
+        LI->setAlignment(std::max(A, LI->getAlign()));
+        continue;
+      }
+      if (auto *SI = dyn_cast<StoreInst>(U)) {
+        SI->setAlignment(std::max(A, SI->getAlign()));
+        continue;
+      }
+      if (auto *AI = dyn_cast<AtomicRMWInst>(U)) {
+        AI->setAlignment(std::max(A, AI->getAlign()));
+        continue;
+      }
+      if (auto *AI = dyn_cast<AtomicCmpXchgInst>(U)) {
+        AI->setAlignment(std::max(A, AI->getAlign()));
+        continue;
+      }
+      if (auto *GEP = dyn_cast<GetElementPtrInst>(U)) {
+        unsigned BitWidth = DL.getIndexTypeSizeInBits(GEP->getType());
+        APInt Off(BitWidth, 0);
+        if (GEP->getPointerOperand() == Ptr &&
+            GEP->accumulateConstantOffset(DL, Off)) {
+          Align GA = commonAlignment(A, Off.getLimitedValue());
+          refineUsesAlignment(GEP, GA, DL, MaxDepth - 1);
+        }
+        continue;
+      }
+      if (auto *I = dyn_cast<Instruction>(U)) {
+        if (I->getOpcode() == Instruction::BitCast ||
+            I->getOpcode() == Instruction::AddrSpaceCast)
+          refineUsesAlignment(I, A, DL, MaxDepth - 1);
+      }
+    }
+  }
 };
 
 } // namespace
 char AMDGPULowerModuleLDS::ID = 0;
 
 char &llvm::AMDGPULowerModuleLDSID = AMDGPULowerModuleLDS::ID;
 
 INITIALIZE_PASS(AMDGPULowerModuleLDS, DEBUG_TYPE,

llvm/test/CodeGen/AMDGPU/ds_read2.ll

 
 @bar = addrspace(3) global [4 x i64] undef, align 4
 
 define amdgpu_kernel void @load_misaligned64_constant_offsets(i64 addrspace(1)* %out) {
 ; CI-LABEL: load_misaligned64_constant_offsets:
 ; CI:       ; %bb.0:
 ; CI-NEXT:    v_mov_b32_e32 v0, 0
 ; CI-NEXT:    s_mov_b32 m0, -1
-; CI-NEXT:    ds_read2_b64 v[0:3], v0 offset1:1
+; CI-NEXT:    ds_read_b128 v[0:3], v0
 ; CI-NEXT:    s_load_dwordx2 s[0:1], s[0:1], 0x9
 ; CI-NEXT:    s_mov_b32 s3, 0xf000
 ; CI-NEXT:    s_mov_b32 s2, -1
 ; CI-NEXT:    s_waitcnt lgkmcnt(0)
 ; CI-NEXT:    v_add_i32_e32 v0, vcc, v0, v2
 ; CI-NEXT:    v_addc_u32_e32 v1, vcc, v1, v3, vcc
 ; CI-NEXT:    buffer_store_dwordx2 v[0:1], off, s[0:3], 0
 ; CI-NEXT:    s_endpgm
 ;
-; GFX9-ALIGNED-LABEL: load_misaligned64_constant_offsets:
-; GFX9-ALIGNED:       ; %bb.0:
-; GFX9-ALIGNED-NEXT:    v_mov_b32_e32 v4, 0
-; GFX9-ALIGNED-NEXT:    ds_read2_b64 v[0:3], v4 offset1:1
-; GFX9-ALIGNED-NEXT:    s_load_dwordx2 s[0:1], s[0:1], 0x24
-; GFX9-ALIGNED-NEXT:    s_waitcnt lgkmcnt(0)
-; GFX9-ALIGNED-NEXT:    v_add_co_u32_e32 v0, vcc, v0, v2
-; GFX9-ALIGNED-NEXT:    v_addc_co_u32_e32 v1, vcc, v1, v3, vcc
-; GFX9-ALIGNED-NEXT:    global_store_dwordx2 v4, v[0:1], s[0:1]
-; GFX9-ALIGNED-NEXT:    s_endpgm
-;
-; GFX9-UNALIGNED-LABEL: load_misaligned64_constant_offsets:
-; GFX9-UNALIGNED:       ; %bb.0:
-; GFX9-UNALIGNED-NEXT:    v_mov_b32_e32 v4, 0
-; GFX9-UNALIGNED-NEXT:    ds_read_b128 v[0:3], v4
-; GFX9-UNALIGNED-NEXT:    s_load_dwordx2 s[0:1], s[0:1], 0x24
-; GFX9-UNALIGNED-NEXT:    s_waitcnt lgkmcnt(0)
-; GFX9-UNALIGNED-NEXT:    v_add_co_u32_e32 v0, vcc, v0, v2
-; GFX9-UNALIGNED-NEXT:    v_addc_co_u32_e32 v1, vcc, v1, v3, vcc
-; GFX9-UNALIGNED-NEXT:    global_store_dwordx2 v4, v[0:1], s[0:1]
-; GFX9-UNALIGNED-NEXT:    s_endpgm
+; GFX9-LABEL: load_misaligned64_constant_offsets:
+; GFX9:       ; %bb.0:
+; GFX9-NEXT:    v_mov_b32_e32 v4, 0
+; GFX9-NEXT:    ds_read_b128 v[0:3], v4
+; GFX9-NEXT:    s_load_dwordx2 s[0:1], s[0:1], 0x24
+; GFX9-NEXT:    s_waitcnt lgkmcnt(0)
+; GFX9-NEXT:    v_add_co_u32_e32 v0, vcc, v0, v2
+; GFX9-NEXT:    v_addc_co_u32_e32 v1, vcc, v1, v3, vcc
+; GFX9-NEXT:    global_store_dwordx2 v4, v[0:1], s[0:1]
+; GFX9-NEXT:    s_endpgm
   %val0 = load i64, i64 addrspace(3)* getelementptr inbounds ([4 x i64], [4 x i64] addrspace(3)* @bar, i32 0, i32 0), align 4
   %val1 = load i64, i64 addrspace(3)* getelementptr inbounds ([4 x i64], [4 x i64] addrspace(3)* @bar, i32 0, i32 1), align 4
   %sum = add i64 %val0, %val1
   store i64 %sum, i64 addrspace(1)* %out, align 8
   ret void
 }
 
 @bar.large = addrspace(3) global [4096 x i64] undef, align 4

llvm/test/CodeGen/AMDGPU/ds_write2.ll

; GFX9-NEXT:    s_endpgm
   ret void
 }
 
 @bar = addrspace(3) global [4 x i64] undef, align 4
 
 define amdgpu_kernel void @store_misaligned64_constant_offsets() {
 ; CI-LABEL: store_misaligned64_constant_offsets:
 ; CI:       ; %bb.0:
-; CI-NEXT:    s_movk_i32 s0, 0x7b
-; CI-NEXT:    s_mov_b32 s1, 0
-; CI-NEXT:    v_mov_b32_e32 v0, s0
-; CI-NEXT:    v_mov_b32_e32 v2, 0
-; CI-NEXT:    v_mov_b32_e32 v1, s1
+; CI-NEXT:    v_mov_b32_e32 v0, 0x7b
+; CI-NEXT:    v_mov_b32_e32 v1, 0
+; CI-NEXT:    v_mov_b32_e32 v2, v0
+; CI-NEXT:    v_mov_b32_e32 v3, v1
 ; CI-NEXT:    s_mov_b32 m0, -1
-; CI-NEXT:    ds_write2_b64 v2, v[0:1], v[0:1] offset1:1
+; CI-NEXT:    ds_write_b128 v1, v[0:3]
 ; CI-NEXT:    s_endpgm
 ;
-; GFX9-ALIGNED-LABEL: store_misaligned64_constant_offsets:
-; GFX9-ALIGNED:       ; %bb.0:
-; GFX9-ALIGNED-NEXT:    s_movk_i32 s0, 0x7b
-; GFX9-ALIGNED-NEXT:    s_mov_b32 s1, 0
-; GFX9-ALIGNED-NEXT:    v_mov_b32_e32 v0, s0
-; GFX9-ALIGNED-NEXT:    v_mov_b32_e32 v2, 0
-; GFX9-ALIGNED-NEXT:    v_mov_b32_e32 v1, s1
-; GFX9-ALIGNED-NEXT:    ds_write2_b64 v2, v[0:1], v[0:1] offset1:1
-; GFX9-ALIGNED-NEXT:    s_endpgm
-;
-; GFX9-UNALIGNED-LABEL: store_misaligned64_constant_offsets:
-; GFX9-UNALIGNED:       ; %bb.0:
-; GFX9-UNALIGNED-NEXT:    v_mov_b32_e32 v0, 0x7b
-; GFX9-UNALIGNED-NEXT:    v_mov_b32_e32 v1, 0
-; GFX9-UNALIGNED-NEXT:    v_mov_b32_e32 v2, v0
-; GFX9-UNALIGNED-NEXT:    v_mov_b32_e32 v3, v1
-; GFX9-UNALIGNED-NEXT:    ds_write_b128 v1, v[0:3]
-; GFX9-UNALIGNED-NEXT:    s_endpgm
+; GFX9-LABEL: store_misaligned64_constant_offsets:
+; GFX9:       ; %bb.0:
+; GFX9-NEXT:    v_mov_b32_e32 v0, 0x7b
+; GFX9-NEXT:    v_mov_b32_e32 v1, 0
+; GFX9-NEXT:    v_mov_b32_e32 v2, v0
+; GFX9-NEXT:    v_mov_b32_e32 v3, v1
+; GFX9-NEXT:    ds_write_b128 v1, v[0:3]
+; GFX9-NEXT:    s_endpgm
   store i64 123, i64 addrspace(3)* getelementptr inbounds ([4 x i64], [4 x i64] addrspace(3)* @bar, i32 0, i32 0), align 4
   store i64 123, i64 addrspace(3)* getelementptr inbounds ([4 x i64], [4 x i64] addrspace(3)* @bar, i32 0, i32 1), align 4
   ret void
 }
 
 @bar.large = addrspace(3) global [4096 x i64] undef, align 4
 
 define amdgpu_kernel void @store_misaligned64_constant_large_offsets() {

llvm/test/CodeGen/AMDGPU/lower-kernel-and-module-lds.ll

 ; CHECK: @llvm.amdgcn.kernel.k1.lds = internal addrspace(3) global %llvm.amdgcn.kernel.k1.lds.t undef, align 16
 ; CHECK: @llvm.amdgcn.kernel..lds = internal addrspace(3) global %llvm.amdgcn.kernel..lds.t undef, align 2
 ; CHECK: @llvm.amdgcn.kernel..lds.1 = internal addrspace(3) global %llvm.amdgcn.kernel..lds.t.0 undef, align 4
 ;.
 define amdgpu_kernel void @k0() {
 ; CHECK-LABEL: @k0(
 ; CHECK-NEXT:    call void @llvm.donothing() [ "ExplicitUse"(%llvm.amdgcn.module.lds.t addrspace(3)* @llvm.amdgcn.module.lds) ]
 ; CHECK-NEXT:    %lds.size.1.align.1.bc = bitcast [1 x i8] addrspace(3)* getelementptr inbounds (%llvm.amdgcn.module.lds.t, %llvm.amdgcn.module.lds.t addrspace(3)* @llvm.amdgcn.module.lds, i32 0, i32 1) to i8 addrspace(3)*
-; CHECK-NEXT:    store i8 1, i8 addrspace(3)* %lds.size.1.align.1.bc, align 1
+; CHECK-NEXT:    store i8 1, i8 addrspace(3)* %lds.size.1.align.1.bc, align 8
 ; CHECK-NEXT:    %lds.size.2.align.2.bc = bitcast [2 x i8] addrspace(3)* getelementptr inbounds (%llvm.amdgcn.kernel.k0.lds.t, %llvm.amdgcn.kernel.k0.lds.t addrspace(3)* @llvm.amdgcn.kernel.k0.lds, i32 0, i32 2) to i8 addrspace(3)*
-; CHECK-NEXT:    store i8 2, i8 addrspace(3)* %lds.size.2.align.2.bc, align 2
+; CHECK-NEXT:    store i8 2, i8 addrspace(3)* %lds.size.2.align.2.bc, align 4
 ; CHECK-NEXT:    %lds.size.4.align.4.bc = bitcast [4 x i8] addrspace(3)* getelementptr inbounds (%llvm.amdgcn.kernel.k0.lds.t, %llvm.amdgcn.kernel.k0.lds.t addrspace(3)* @llvm.amdgcn.kernel.k0.lds, i32 0, i32 1) to i8 addrspace(3)*
-; CHECK-NEXT:    store i8 4, i8 addrspace(3)* %lds.size.4.align.4.bc, align 4
+; CHECK-NEXT:    store i8 4, i8 addrspace(3)* %lds.size.4.align.4.bc, align 16
 ; CHECK-NEXT:    %lds.size.16.align.16.bc = bitcast [16 x i8] addrspace(3)* getelementptr inbounds (%llvm.amdgcn.kernel.k0.lds.t, %llvm.amdgcn.kernel.k0.lds.t addrspace(3)* @llvm.amdgcn.kernel.k0.lds, i32 0, i32 0) to i8 addrspace(3)*
 ; CHECK-NEXT:    store i8 16, i8 addrspace(3)* %lds.size.16.align.16.bc, align 16
 ; CHECK-NEXT:    ret void
 ;
   %lds.size.1.align.1.bc = bitcast [1 x i8] addrspace(3)* @lds.size.1.align.1 to i8 addrspace(3)*
   store i8 1, i8 addrspace(3)* %lds.size.1.align.1.bc, align 1
 
   %lds.size.2.align.2.bc = bitcast [2 x i8] addrspace(3)* @lds.size.2.align.2 to i8 addrspace(3)*
   store i8 2, i8 addrspace(3)* %lds.size.2.align.2.bc, align 2
 
   %lds.size.4.align.4.bc = bitcast [4 x i8] addrspace(3)* @lds.size.4.align.4 to i8 addrspace(3)*
   store i8 4, i8 addrspace(3)* %lds.size.4.align.4.bc, align 4
 
   %lds.size.16.align.16.bc = bitcast [16 x i8] addrspace(3)* @lds.size.16.align.16 to i8 addrspace(3)*
   store i8 16, i8 addrspace(3)* %lds.size.16.align.16.bc, align 16
 
   ret void
 }
 
 define amdgpu_kernel void @k1() {
 ; CHECK-LABEL: @k1(
 ; CHECK-NEXT:    call void @llvm.donothing() [ "ExplicitUse"(%llvm.amdgcn.module.lds.t addrspace(3)* @llvm.amdgcn.module.lds) ]
 ; CHECK-NEXT:    %lds.size.2.align.2.bc = bitcast [2 x i8] addrspace(3)* getelementptr inbounds (%llvm.amdgcn.kernel.k1.lds.t, %llvm.amdgcn.kernel.k1.lds.t addrspace(3)* @llvm.amdgcn.kernel.k1.lds, i32 0, i32 2) to i8 addrspace(3)*
-; CHECK-NEXT:    store i8 2, i8 addrspace(3)* %lds.size.2.align.2.bc, align 2
+; CHECK-NEXT:    store i8 2, i8 addrspace(3)* %lds.size.2.align.2.bc, align 4
 ; CHECK-NEXT:    %lds.size.4.align.4.bc = bitcast [4 x i8] addrspace(3)* getelementptr inbounds (%llvm.amdgcn.kernel.k1.lds.t, %llvm.amdgcn.kernel.k1.lds.t addrspace(3)* @llvm.amdgcn.kernel.k1.lds, i32 0, i32 1) to i8 addrspace(3)*
-; CHECK-NEXT:    store i8 4, i8 addrspace(3)* %lds.size.4.align.4.bc, align 4
+; CHECK-NEXT:    store i8 4, i8 addrspace(3)* %lds.size.4.align.4.bc, align 16
 ; CHECK-NEXT:    %lds.size.16.align.16.bc = bitcast [16 x i8] addrspace(3)* getelementptr inbounds (%llvm.amdgcn.kernel.k1.lds.t, %llvm.amdgcn.kernel.k1.lds.t addrspace(3)* @llvm.amdgcn.kernel.k1.lds, i32 0, i32 0) to i8 addrspace(3)*
 ; CHECK-NEXT:    store i8 16, i8 addrspace(3)* %lds.size.16.align.16.bc, align 16
 ; CHECK-NEXT:    ret void
 ;
   %lds.size.2.align.2.bc = bitcast [2 x i8] addrspace(3)* @lds.size.2.align.2 to i8 addrspace(3)*
   store i8 2, i8 addrspace(3)* %lds.size.2.align.2.bc, align 2
 
   %lds.size.4.align.4.bc = bitcast [4 x i8] addrspace(3)* @lds.size.4.align.4 to i8 addrspace(3)*
;
   store i8 4, i8 addrspace(3)* %lds.size.4.align.4.bc, align 4
 
   ret void
 }
 
 define void @f0() {
 ; CHECK-LABEL: @f0(
 ; CHECK-NEXT:    %lds.size.1.align.1.bc = bitcast [1 x i8] addrspace(3)* getelementptr inbounds (%llvm.amdgcn.module.lds.t, %llvm.amdgcn.module.lds.t addrspace(3)* @llvm.amdgcn.module.lds, i32 0, i32 1) to i8 addrspace(3)*
-; CHECK-NEXT:    store i8 1, i8 addrspace(3)* %lds.size.1.align.1.bc, align 1
+; CHECK-NEXT:    store i8 1, i8 addrspace(3)* %lds.size.1.align.1.bc, align 8
 ; CHECK-NEXT:    %lds.size.8.align.8.bc = bitcast [8 x i8] addrspace(3)* getelementptr inbounds (%llvm.amdgcn.module.lds.t, %llvm.amdgcn.module.lds.t addrspace(3)* @llvm.amdgcn.module.lds, i32 0, i32 0) to i8 addrspace(3)*
-; CHECK-NEXT:    store i8 8, i8 addrspace(3)* %lds.size.8.align.8.bc, align 4
+; CHECK-NEXT:    store i8 8, i8 addrspace(3)* %lds.size.8.align.8.bc, align 8
 ; CHECK-NEXT:    ret void
 ;
   %lds.size.1.align.1.bc = bitcast [1 x i8] addrspace(3)* @lds.size.1.align.1 to i8 addrspace(3)*
   store i8 1, i8 addrspace(3)* %lds.size.1.align.1.bc, align 1
 
   %lds.size.8.align.8.bc = bitcast [8 x i8] addrspace(3)* @lds.size.8.align.8 to i8 addrspace(3)*
   store i8 8, i8 addrspace(3)* %lds.size.8.align.8.bc, align 4
 
   ret void
 }
 ;.
 ; CHECK: attributes #0 = { nofree nosync nounwind readnone willreturn }
 ;.

llvm/test/CodeGen/AMDGPU/lower-kernel-lds-constexpr.ll

 ; CHECK-LABEL: @k3(
 ; CHECK-NEXT:    %1 = getelementptr inbounds [32 x i8], [32 x i8] addrspace(3)* getelementptr inbounds (%llvm.amdgcn.kernel.k3.lds.t, %llvm.amdgcn.kernel.k3.lds.t addrspace(3)* @llvm.amdgcn.kernel.k3.lds, i32 0, i32 0), i32 0, i32 16
 ; CHECK-NEXT:    %2 = bitcast i8 addrspace(3)* %1 to i64 addrspace(3)*
 ; CHECK-NEXT:    %ptr1 = addrspacecast i64 addrspace(3)* %2 to i64*
 ; CHECK-NEXT:    store i64 1, i64* %ptr1, align 1
 ; CHECK-NEXT:    %3 = getelementptr inbounds [32 x i8], [32 x i8] addrspace(3)* getelementptr inbounds (%llvm.amdgcn.kernel.k3.lds.t, %llvm.amdgcn.kernel.k3.lds.t addrspace(3)* @llvm.amdgcn.kernel.k3.lds, i32 0, i32 0), i32 0, i32 24
 ; CHECK-NEXT:    %4 = bitcast i8 addrspace(3)* %3 to i64 addrspace(3)*
 ; CHECK-NEXT:    %ptr2 = addrspacecast i64 addrspace(3)* %4 to i64*
-; CHECK-NEXT:    store i64 2, i64* %ptr2, align 1
+; CHECK-NEXT:    store i64 2, i64* %ptr2, align 8
 ; CHECK-NEXT:    ret void
 ;
   %ptr1 = addrspacecast i64 addrspace(3)* bitcast (i8 addrspace(3)* getelementptr inbounds ([32 x i8], [32 x i8] addrspace(3)* @lds.3, i32 0, i32 16) to i64 addrspace(3)*) to i64*
   store i64 1, i64* %ptr1, align 1
   %ptr2 = addrspacecast i64 addrspace(3)* bitcast (i8 addrspace(3)* getelementptr inbounds ([32 x i8], [32 x i8] addrspace(3)* @lds.3, i32 0, i32 24) to i64 addrspace(3)*) to i64*
   store i64 2, i64* %ptr2, align 1
   ret void
 }

llvm/test/CodeGen/AMDGPU/lower-kernel-lds-global-uses.ll

 ; CHECK: @llvm.amdgcn.kernel.k0.lds = internal addrspace(3) global %llvm.amdgcn.kernel.k0.lds.t undef, align 4
 
 ; CHECK: @llvm.used = appending global [1 x i8*] [i8* addrspacecast (i8 addrspace(3)* bitcast (i16 addrspace(3)* @lds.5 to i8 addrspace(3)*) to i8*)], section "llvm.metadata"
 ; CHECK: @llvm.compiler.used = appending global [2 x i8*] [i8* addrspacecast (i8 addrspace(1)* bitcast (i64* addrspace(1)* @gptr.4 to i8 addrspace(1)*) to i8*), i8* addrspacecast (i8 addrspace(3)* bitcast (i32 addrspace(3)* @lds.6 to i8 addrspace(3)*) to i8*)], section "llvm.metadata"
 @llvm.used = appending global [2 x i8*] [i8* addrspacecast (i8 addrspace(3)* bitcast (i16 addrspace(3)* @lds.1 to i8 addrspace(3)*) to i8*), i8* addrspacecast (i8 addrspace(3)* bitcast (i16 addrspace(3)* @lds.5 to i8 addrspace(3)*) to i8*)], section "llvm.metadata"
 @llvm.compiler.used = appending global [3 x i8*] [i8* addrspacecast (i8 addrspace(3)* bitcast (i32 addrspace(3)* @lds.2 to i8 addrspace(3)*) to i8*), i8* addrspacecast (i8 addrspace(1)* bitcast (i64* addrspace(1)* @gptr.4 to i8 addrspace(1)*) to i8*), i8* addrspacecast (i8 addrspace(3)* bitcast (i32 addrspace(3)* @lds.6 to i8 addrspace(3)*) to i8*)], section "llvm.metadata"
 
 ; CHECK-LABEL: @k0()
-; CHECK:   %ld.lds.1 = load i16, i16 addrspace(3)* getelementptr inbounds (%llvm.amdgcn.kernel.k0.lds.t, %llvm.amdgcn.kernel.k0.lds.t addrspace(3)* @llvm.amdgcn.kernel.k0.lds, i32 0, i32 1), align 2
+; CHECK:   %ld.lds.1 = load i16, i16 addrspace(3)* getelementptr inbounds (%llvm.amdgcn.kernel.k0.lds.t, %llvm.amdgcn.kernel.k0.lds.t addrspace(3)* @llvm.amdgcn.kernel.k0.lds, i32 0, i32 1), align 4
 ; CHECK:   %ld.lds.2 = load i32, i32 addrspace(3)* getelementptr inbounds (%llvm.amdgcn.kernel.k0.lds.t, %llvm.amdgcn.kernel.k0.lds.t addrspace(3)* @llvm.amdgcn.kernel.k0.lds, i32 0, i32 0), align 4
 ; CHECK:   %ld.lds.3 = load i64, i64 addrspace(3)* @lds.3, align 4
 ; CHECK:   %ld.lds.4 = load float, float addrspace(3)* @lds.4, align 4
 ; CHECK:   ret void
 define amdgpu_kernel void @k0() {
   %ld.lds.1 = load i16, i16 addrspace(3)* @lds.1
   %ld.lds.2 = load i32, i32 addrspace(3)* @lds.2
   %ld.lds.3 = load i64, i64 addrspace(3)* @lds.3
   %ld.lds.4 = load float, float addrspace(3)* @lds.4
   ret void
 }

llvm/test/CodeGen/AMDGPU/lower-kernel-lds-super-align.ll

 ; RUN: opt -S -mtriple=amdgcn-- -amdgpu-lower-module-lds < %s | FileCheck --check-prefixes=CHECK,SUPER-ALIGN_ON %s
 ; RUN: opt -S -mtriple=amdgcn-- -passes=amdgpu-lower-module-lds < %s | FileCheck --check-prefixes=CHECK,SUPER-ALIGN_ON %s
 ; RUN: opt -S -mtriple=amdgcn-- -amdgpu-lower-module-lds --amdgpu-super-align-lds-globals=false < %s | FileCheck --check-prefixes=CHECK,SUPER-ALIGN_OFF %s
 ; RUN: opt -S -mtriple=amdgcn-- -passes=amdgpu-lower-module-lds --amdgpu-super-align-lds-globals=false < %s | FileCheck --check-prefixes=CHECK,SUPER-ALIGN_OFF %s
 
 ; CHECK: %llvm.amdgcn.kernel.k1.lds.t = type { [32 x i8] }
+; CHECK: %llvm.amdgcn.kernel.k2.lds.t = type { i16, [2 x i8], i16 }
+; CHECK: %llvm.amdgcn.kernel.k3.lds.t = type { [32 x i64], [32 x i32] }
 
 ; CHECK-NOT: @lds.1
 @lds.1 = internal unnamed_addr addrspace(3) global [32 x i8] undef, align 1
 
 ; SUPER-ALIGN_ON: @llvm.amdgcn.kernel.k1.lds = internal addrspace(3) global %llvm.amdgcn.kernel.k1.lds.t undef, align 16
 ; SUPER-ALIGN_OFF: @llvm.amdgcn.kernel.k1.lds = internal addrspace(3) global %llvm.amdgcn.kernel.k1.lds.t undef, align 1
 
+; CHECK: @llvm.amdgcn.kernel.k2.lds = internal addrspace(3) global %llvm.amdgcn.kernel.k2.lds.t undef, align 4
+; SUPER-ALIGN_ON:  @llvm.amdgcn.kernel.k3.lds = internal addrspace(3) global %llvm.amdgcn.kernel.k3.lds.t undef, align 16
+; SUPER-ALIGN_OFF: @llvm.amdgcn.kernel.k3.lds = internal addrspace(3) global %llvm.amdgcn.kernel.k3.lds.t undef, align 8
+
 ; CHECK-LABEL: @k1
 ; CHECK:  %1 = getelementptr inbounds [32 x i8], [32 x i8] addrspace(3)* getelementptr inbounds (%llvm.amdgcn.kernel.k1.lds.t, %llvm.amdgcn.kernel.k1.lds.t addrspace(3)* @llvm.amdgcn.kernel.k1.lds, i32 0, i32 0), i32 0, i32 0
 ; CHECK:  %2 = addrspacecast i8 addrspace(3)* %1 to i8*
 ; CHECK:  %ptr = getelementptr inbounds i8, i8* %2, i64 %x
 ; CHECK:  store i8 1, i8* %ptr, align 1
 define amdgpu_kernel void @k1(i64 %x) {
   %ptr = getelementptr inbounds i8, i8* addrspacecast ([32 x i8] addrspace(3)* @lds.1 to i8*), i64 %x
   store i8 1, i8 addrspace(0)* %ptr, align 1
   ret void
 }
+
+@lds.2 = internal unnamed_addr addrspace(3) global i16 undef, align 4
+@lds.3 = internal unnamed_addr addrspace(3) global i16 undef, align 4
+
+; Check that alignment is propagated to uses for scalar variables.
+
+; CHECK-LABEL: @k2
+; CHECK: store i16 1, i16 addrspace(3)* getelementptr inbounds (%llvm.amdgcn.kernel.k2.lds.t, %llvm.amdgcn.kernel.k2.lds.t addrspace(3)* @llvm.amdgcn.kernel.k2.lds, i32 0, i32 0), align 4
+; CHECK: store i16 2, i16 addrspace(3)* getelementptr inbounds (%llvm.amdgcn.kernel.k2.lds.t, %llvm.amdgcn.kernel.k2.lds.t addrspace(3)* @llvm.amdgcn.kernel.k2.lds, i32 0, i32 2), align 4
+define amdgpu_kernel void @k2() {
+  store i16 1, i16 addrspace(3)* @lds.2, align 2
+  store i16 2, i16 addrspace(3)* @lds.3, align 2
+  ret void
+}
+
+@lds.4 = internal unnamed_addr addrspace(3) global [32 x i64] undef, align 8
+@lds.5 = internal unnamed_addr addrspace(3) global [32 x i32] undef, align 4
+
+; Check that alignment is propagated to uses for arrays.
+
+; CHECK-LABEL: @k3
+; CHECK:  store i32 1, i32 addrspace(3)* %ptr1, align 8
+; CHECK:  store i32 2, i32 addrspace(3)* %ptr2, align 4
+; SUPER-ALIGN_ON:  store i32 3, i32 addrspace(3)* %ptr3, align 16
+; SUPER-ALIGN_OFF: store i32 3, i32 addrspace(3)* %ptr3, align 8
+; CHECK:  store i32 4, i32 addrspace(3)* %ptr4, align 4
+; CHECK:  store i32 5, i32 addrspace(3)* %ptr5, align 4
+; CHECK:  %load1 = load i32, i32 addrspace(3)* %ptr1, align 8
+; CHECK:  %load2 = load i32, i32 addrspace(3)* %ptr2, align 4
+; SUPER-ALIGN_ON:   %load3 = load i32, i32 addrspace(3)* %ptr3, align 16
+; SUPER-ALIGN_OFF:  %load3 = load i32, i32 addrspace(3)* %ptr3, align 8
+; CHECK:  %load4 = load i32, i32 addrspace(3)* %ptr4, align 4
+; CHECK:  %load5 = load i32, i32 addrspace(3)* %ptr5, align 4
+; CHECK:  %val1 = atomicrmw volatile add i32 addrspace(3)* %ptr1, i32 1 monotonic, align 8
+; CHECK:  %val2 = cmpxchg volatile i32 addrspace(3)* %ptr1, i32 1, i32 2 monotonic monotonic, align 8
+; CHECK:  %ptr1.bc = bitcast i32 addrspace(3)* %ptr1 to i16 addrspace(3)*
+; CHECK:  %ptr2.bc = bitcast i32 addrspace(3)* %ptr2 to i16 addrspace(3)*
+; CHECK:  %ptr3.bc = bitcast i32 addrspace(3)* %ptr3 to i16 addrspace(3)*
+; CHECK:  %ptr4.bc = bitcast i32 addrspace(3)* %ptr4 to i16 addrspace(3)*
+; CHECK:  store i16 11, i16 addrspace(3)* %ptr1.bc, align 8
+; CHECK:  store i16 12, i16 addrspace(3)* %ptr2.bc, align 4
+; SUPER-ALIGN_ON:   store i16 13, i16 addrspace(3)* %ptr3.bc, align 16
+; SUPER-ALIGN_OFF:  store i16 13, i16 addrspace(3)* %ptr3.bc, align 8
+; CHECK:  store i16 14, i16 addrspace(3)* %ptr4.bc, align 4
+; CHECK:  %ptr1.ac = addrspacecast i32 addrspace(3)* %ptr1 to i32*
+; CHECK:  %ptr2.ac = addrspacecast i32 addrspace(3)* %ptr2 to i32*
+; CHECK:  %ptr3.ac = addrspacecast i32 addrspace(3)* %ptr3 to i32*
+; CHECK:  %ptr4.ac = addrspacecast i32 addrspace(3)* %ptr4 to i32*
+; CHECK:  store i32 21, i32* %ptr1.ac, align 8
+; CHECK:  store i32 22, i32* %ptr2.ac, align 4
+; SUPER-ALIGN_ON:   store i32 23, i32* %ptr3.ac, align 16
+; SUPER-ALIGN_OFF:  store i32 23, i32* %ptr3.ac, align 8
+; CHECK:  store i32 24, i32* %ptr4.ac, align 4
+define amdgpu_kernel void @k3(i64 %x) {
+  %ptr0 = getelementptr inbounds i64, i64 addrspace(3)* bitcast ([32 x i64] addrspace(3)* @lds.4 to i64 addrspace(3)*), i64 0
+  store i64 0, i64 addrspace(3)* %ptr0, align 8
+
+  %ptr1 = getelementptr inbounds i32, i32 addrspace(3)* bitcast ([32 x i32] addrspace(3)* @lds.5 to i32 addrspace(3)*), i64 2
+  %ptr2 = getelementptr inbounds i32, i32 addrspace(3)* bitcast ([32 x i32] addrspace(3)* @lds.5 to i32 addrspace(3)*), i64 3
+  %ptr3 = getelementptr inbounds i32, i32 addrspace(3)* bitcast ([32 x i32] addrspace(3)* @lds.5 to i32 addrspace(3)*), i64 4
+  %ptr4 = getelementptr inbounds i32, i32 addrspace(3)* bitcast ([32 x i32] addrspace(3)* @lds.5 to i32 addrspace(3)*), i64 5
+  %ptr5 = getelementptr inbounds i32, i32 addrspace(3)* bitcast ([32 x i32] addrspace(3)* @lds.5 to i32 addrspace(3)*), i64 %x
+
+  store i32 1, i32 addrspace(3)* %ptr1, align 4
+  store i32 2, i32 addrspace(3)* %ptr2, align 4
+  store i32 3, i32 addrspace(3)* %ptr3, align 4
+  store i32 4, i32 addrspace(3)* %ptr4, align 4
+  store i32 5, i32 addrspace(3)* %ptr5, align 4
+
+  %load1 = load i32, i32 addrspace(3)* %ptr1, align 4
+  %load2 = load i32, i32 addrspace(3)* %ptr2, align 4
+  %load3 = load i32, i32 addrspace(3)* %ptr3, align 4
+  %load4 = load i32, i32 addrspace(3)* %ptr4, align 4
+  %load5 = load i32, i32 addrspace(3)* %ptr5, align 4
+
+  %val1 = atomicrmw volatile add i32 addrspace(3)* %ptr1, i32 1 monotonic, align 4
+  %val2 = cmpxchg volatile i32 addrspace(3)* %ptr1, i32 1, i32 2 monotonic monotonic, align 4
+
+  %ptr1.bc = bitcast i32 addrspace(3)* %ptr1 to i16 addrspace(3)*
+  %ptr2.bc = bitcast i32 addrspace(3)* %ptr2 to i16 addrspace(3)*
+  %ptr3.bc = bitcast i32 addrspace(3)* %ptr3 to i16 addrspace(3)*
+  %ptr4.bc = bitcast i32 addrspace(3)* %ptr4 to i16 addrspace(3)*
+
+  store i16 11, i16 addrspace(3)* %ptr1.bc, align 2
+  store i16 12, i16 addrspace(3)* %ptr2.bc, align 2
+  store i16 13, i16 addrspace(3)* %ptr3.bc, align 2
+  store i16 14, i16 addrspace(3)* %ptr4.bc, align 2
+
+  %ptr1.ac = addrspacecast i32 addrspace(3)* %ptr1 to i32*
+  %ptr2.ac = addrspacecast i32 addrspace(3)* %ptr2 to i32*
+  %ptr3.ac = addrspacecast i32 addrspace(3)* %ptr3 to i32*
+  %ptr4.ac = addrspacecast i32 addrspace(3)* %ptr4 to i32*
+
+  store i32 21, i32* %ptr1.ac, align 4
+  store i32 22, i32* %ptr2.ac, align 4
+  store i32 23, i32* %ptr3.ac, align 4
+  store i32 24, i32* %ptr4.ac, align 4
+
+  ret void
+}

llvm/test/CodeGen/AMDGPU/lower-kernel-lds.ll

 ;.
 ; CHECK: @lds.size.8.align.8 = internal unnamed_addr addrspace(3) global [8 x i8] undef, align 8
 ; CHECK: @llvm.amdgcn.kernel.k0.lds = internal addrspace(3) global %llvm.amdgcn.kernel.k0.lds.t undef, align 16
 ; CHECK: @llvm.amdgcn.kernel.k1.lds = internal addrspace(3) global %llvm.amdgcn.kernel.k1.lds.t undef, align 16
 ;.
 define amdgpu_kernel void @k0() {
 ; CHECK-LABEL: @k0(
 ; CHECK-NEXT:    %lds.size.1.align.1.bc = bitcast [1 x i8] addrspace(3)* getelementptr inbounds (%llvm.amdgcn.kernel.k0.lds.t, %llvm.amdgcn.kernel.k0.lds.t addrspace(3)* @llvm.amdgcn.kernel.k0.lds, i32 0, i32 3) to i8 addrspace(3)*
-; CHECK-NEXT:    store i8 1, i8 addrspace(3)* %lds.size.1.align.1.bc, align 1
+; CHECK-NEXT:    store i8 1, i8 addrspace(3)* %lds.size.1.align.1.bc, align 2
 ; CHECK-NEXT:    %lds.size.2.align.2.bc = bitcast [2 x i8] addrspace(3)* getelementptr inbounds (%llvm.amdgcn.kernel.k0.lds.t, %llvm.amdgcn.kernel.k0.lds.t addrspace(3)* @llvm.amdgcn.kernel.k0.lds, i32 0, i32 2) to i8 addrspace(3)*
-; CHECK-NEXT:    store i8 2, i8 addrspace(3)* %lds.size.2.align.2.bc, align 2
+; CHECK-NEXT:    store i8 2, i8 addrspace(3)* %lds.size.2.align.2.bc, align 4
 ; CHECK-NEXT:    %lds.size.4.align.4.bc = bitcast [4 x i8] addrspace(3)* getelementptr inbounds (%llvm.amdgcn.kernel.k0.lds.t, %llvm.amdgcn.kernel.k0.lds.t addrspace(3)* @llvm.amdgcn.kernel.k0.lds, i32 0, i32 1) to i8 addrspace(3)*
-; CHECK-NEXT:    store i8 4, i8 addrspace(3)* %lds.size.4.align.4.bc, align 4
+; CHECK-NEXT:    store i8 4, i8 addrspace(3)* %lds.size.4.align.4.bc, align 16
 ; CHECK-NEXT:    %lds.size.16.align.16.bc = bitcast [16 x i8] addrspace(3)* getelementptr inbounds (%llvm.amdgcn.kernel.k0.lds.t, %llvm.amdgcn.kernel.k0.lds.t addrspace(3)* @llvm.amdgcn.kernel.k0.lds, i32 0, i32 0) to i8 addrspace(3)*
 ; CHECK-NEXT:    store i8 16, i8 addrspace(3)* %lds.size.16.align.16.bc, align 16
 ; CHECK-NEXT:    ret void
 ;
   %lds.size.1.align.1.bc = bitcast [1 x i8] addrspace(3)* @lds.size.1.align.1 to i8 addrspace(3)*
   store i8 1, i8 addrspace(3)* %lds.size.1.align.1.bc, align 1
 
   %lds.size.2.align.2.bc = bitcast [2 x i8] addrspace(3)* @lds.size.2.align.2 to i8 addrspace(3)*
   store i8 2, i8 addrspace(3)* %lds.size.2.align.2.bc, align 2
 
   %lds.size.4.align.4.bc = bitcast [4 x i8] addrspace(3)* @lds.size.4.align.4 to i8 addrspace(3)*
   store i8 4, i8 addrspace(3)* %lds.size.4.align.4.bc, align 4
 
   %lds.size.16.align.16.bc = bitcast [16 x i8] addrspace(3)* @lds.size.16.align.16 to i8 addrspace(3)*
   store i8 16, i8 addrspace(3)* %lds.size.16.align.16.bc, align 16
 
   ret void
 }
 
 define amdgpu_kernel void @k1() {
 ; CHECK-LABEL: @k1(
 ; CHECK-NEXT:    %lds.size.2.align.2.bc = bitcast [2 x i8] addrspace(3)* getelementptr inbounds (%llvm.amdgcn.kernel.k1.lds.t, %llvm.amdgcn.kernel.k1.lds.t addrspace(3)* @llvm.amdgcn.kernel.k1.lds, i32 0, i32 2) to i8 addrspace(3)*
-; CHECK-NEXT:    store i8 2, i8 addrspace(3)* %lds.size.2.align.2.bc, align 2
+; CHECK-NEXT:    store i8 2, i8 addrspace(3)* %lds.size.2.align.2.bc, align 4
 ; CHECK-NEXT:    %lds.size.4.align.4.bc = bitcast [4 x i8] addrspace(3)* getelementptr inbounds (%llvm.amdgcn.kernel.k1.lds.t, %llvm.amdgcn.kernel.k1.lds.t addrspace(3)* @llvm.amdgcn.kernel.k1.lds, i32 0, i32 1) to i8 addrspace(3)*
-; CHECK-NEXT:    store i8 4, i8 addrspace(3)* %lds.size.4.align.4.bc, align 4
+; CHECK-NEXT:    store i8 4, i8 addrspace(3)* %lds.size.4.align.4.bc, align 16
 ; CHECK-NEXT:    %lds.size.16.align.16.bc = bitcast [16 x i8] addrspace(3)* getelementptr inbounds (%llvm.amdgcn.kernel.k1.lds.t, %llvm.amdgcn.kernel.k1.lds.t addrspace(3)* @llvm.amdgcn.kernel.k1.lds, i32 0, i32 0) to i8 addrspace(3)*
 ; CHECK-NEXT:    store i8 16, i8 addrspace(3)* %lds.size.16.align.16.bc, align 16
 ; CHECK-NEXT:    ret void
 ;
   %lds.size.2.align.2.bc = bitcast [2 x i8] addrspace(3)* @lds.size.2.align.2 to i8 addrspace(3)*
   store i8 2, i8 addrspace(3)* %lds.size.2.align.2.bc, align 2
 
   %lds.size.4.align.4.bc = bitcast [4 x i8] addrspace(3)* @lds.size.4.align.4 to i8 addrspace(3)*
   store i8 4, i8 addrspace(3)* %lds.size.4.align.4.bc, align 4
 
   %lds.size.16.align.16.bc = bitcast [16 x i8] addrspace(3)* @lds.size.16.align.16 to i8 addrspace(3)*
   store i8 16, i8 addrspace(3)* %lds.size.16.align.16.bc, align 16
 
   ret void
 }

llvm/test/CodeGen/AMDGPU/lower-module-lds-used-list.ll

 @llvm.used = appending global [2 x i8*] [i8* addrspacecast (i8 addrspace(3)* bitcast (float addrspace(3)* @tolower to i8 addrspace(3)*) to i8*), i8* addrspacecast (i8 addrspace(1)* bitcast (i64 addrspace(1)* @ignored to i8 addrspace(1)*) to i8*)], section "llvm.metadata"
 
 ; @ignored still in list, @tolower removed, llvm.amdgcn.module.lds appended
 ; CHECK: @llvm.compiler.used = appending global [2 x i8*] [i8* addrspacecast (i8 addrspace(1)* bitcast (i64 addrspace(1)* @ignored to i8 addrspace(1)*) to i8*), i8* addrspacecast (i8 addrspace(3)* bitcast (%llvm.amdgcn.module.lds.t addrspace(3)* @llvm.amdgcn.module.lds to i8 addrspace(3)*) to i8*)], section "llvm.metadata"
 
 @llvm.compiler.used = appending global [2 x i8*] [i8* addrspacecast (i8 addrspace(3)* bitcast (float addrspace(3)* @tolower to i8 addrspace(3)*) to i8*), i8* addrspacecast (i8 addrspace(1)* bitcast (i64 addrspace(1)* @ignored to i8 addrspace(1)*) to i8*)], section "llvm.metadata"
 
 ; CHECK-LABEL: @func()
-; CHECK: %dec = atomicrmw fsub float addrspace(3)* getelementptr inbounds (%llvm.amdgcn.module.lds.t, %llvm.amdgcn.module.lds.t addrspace(3)* @llvm.amdgcn.module.lds, i32 0, i32 0), float 1.000000e+00 monotonic, align 4
+; CHECK: %dec = atomicrmw fsub float addrspace(3)* getelementptr inbounds (%llvm.amdgcn.module.lds.t, %llvm.amdgcn.module.lds.t addrspace(3)* @llvm.amdgcn.module.lds, i32 0, i32 0), float 1.000000e+00 monotonic, align 8
 define void @func() {
   %dec = atomicrmw fsub float addrspace(3)* @tolower, float 1.0 monotonic
   %unused0 = atomicrmw add i64 addrspace(1)* @ignored, i64 1 monotonic
   ret void
 }

llvm/test/CodeGen/AMDGPU/lower-module-lds.ll

 @with_init = addrspace(3) global i64 0
 
 ; Instance of new type, aligned to max of element alignment
 ; CHECK: @llvm.amdgcn.module.lds = internal addrspace(3) global %llvm.amdgcn.module.lds.t undef, align 8
 
 ; Use in func rewritten to access struct at address zero
 ; CHECK-LABEL: @func()
 ; CHECK: %dec = atomicrmw fsub float addrspace(3)* getelementptr inbounds (%llvm.amdgcn.module.lds.t, %llvm.amdgcn.module.lds.t addrspace(3)* @llvm.amdgcn.module.lds, i32 0, i32 0), float 1.0
-; CHECK: %val0 = load i32, i32 addrspace(3)* getelementptr inbounds (%llvm.amdgcn.module.lds.t, %llvm.amdgcn.module.lds.t addrspace(3)* @llvm.amdgcn.module.lds, i32 0, i32 2), align 4
+; CHECK: %val0 = load i32, i32 addrspace(3)* getelementptr inbounds (%llvm.amdgcn.module.lds.t, %llvm.amdgcn.module.lds.t addrspace(3)* @llvm.amdgcn.module.lds, i32 0, i32 2), align 8
 ; CHECK: %val1 = add i32 %val0, 4
-; CHECK: store i32 %val1, i32 addrspace(3)* getelementptr inbounds (%llvm.amdgcn.module.lds.t, %llvm.amdgcn.module.lds.t addrspace(3)* @llvm.amdgcn.module.lds, i32 0, i32 2), align 4
+; CHECK: store i32 %val1, i32 addrspace(3)* getelementptr inbounds (%llvm.amdgcn.module.lds.t, %llvm.amdgcn.module.lds.t addrspace(3)* @llvm.amdgcn.module.lds, i32 0, i32 2), align 8
 ; CHECK: %unused0 = atomicrmw add i64 addrspace(3)* @with_init, i64 1 monotonic
 define void @func() {
   %dec = atomicrmw fsub float addrspace(3)* @var0, float 1.0 monotonic
   %val0 = load i32, i32 addrspace(3)* @var1, align 4
   %val1 = add i32 %val0, 4
   store i32 %val1, i32 addrspace(3)* @var1, align 4
   %unused0 = atomicrmw add i64 addrspace(3)* @with_init, i64 1 monotonic
   ret void
 }
 
 ; This kernel calls a function that uses LDS so needs the block
 ; CHECK-LABEL: @kern_call()
 ; CHECK: call void @llvm.donothing() [ "ExplicitUse"(%llvm.amdgcn.module.lds.t addrspace(3)* @llvm.amdgcn.module.lds) ]
 ; CHECK: call void @func()
-; CHECK: %dec = atomicrmw fsub float addrspace(3)* getelementptr inbounds (%llvm.amdgcn.module.lds.t, %llvm.amdgcn.module.lds.t addrspace(3)* @llvm.amdgcn.module.lds, i32 0, i32 0), float 2.000000e+00 monotonic, align 4
+; CHECK: %dec = atomicrmw fsub float addrspace(3)* getelementptr inbounds (%llvm.amdgcn.module.lds.t, %llvm.amdgcn.module.lds.t addrspace(3)* @llvm.amdgcn.module.lds, i32 0, i32 0), float 2.000000e+00 monotonic, align 8
 define amdgpu_kernel void @kern_call() {
   call void @func()
   %dec = atomicrmw fsub float addrspace(3)* @var0, float 2.0 monotonic
   ret void
 }
 
 ; This kernel does not need to alloc the LDS block as it makes no calls
 ; CHECK-LABEL: @kern_empty()
 ; CHECK: call void @llvm.donothing() [ "ExplicitUse"(%llvm.amdgcn.module.lds.t addrspace(3)* @llvm.amdgcn.module.lds) ]
 define spir_kernel void @kern_empty() {
   ret void
 }