[llvm] [AMDGPU] Promote immediate offset to atomics (PR #94043)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-backend-amdgpu

Author: Stanislav Mekhanoshin (rampitec)

<details>
<summary>Changes</summary>



---
Full diff: https://github.com/llvm/llvm-project/pull/94043.diff


2 Files Affected:

- (modified) llvm/lib/Target/AMDGPU/SILoadStoreOptimizer.cpp (-7) 
- (modified) llvm/test/CodeGen/AMDGPU/promote-constOffset-to-imm.mir (+55) 


``````````diff
diff --git a/llvm/lib/Target/AMDGPU/SILoadStoreOptimizer.cpp b/llvm/lib/Target/AMDGPU/SILoadStoreOptimizer.cpp
index c47eea20563df..8b42d4a1dee7a 100644
--- a/llvm/lib/Target/AMDGPU/SILoadStoreOptimizer.cpp
+++ b/llvm/lib/Target/AMDGPU/SILoadStoreOptimizer.cpp
@@ -2052,9 +2052,6 @@ bool SILoadStoreOptimizer::promoteConstantOffsetToImm(
     MemInfoMap &Visited,
     SmallPtrSet<MachineInstr *, 4> &AnchorList) const {
 
-  if (!(MI.mayLoad() ^ MI.mayStore()))
-    return false;
-
   if (!STM->hasFlatInstOffsets() || !SIInstrInfo::isFLAT(MI))
     return false;
 
@@ -2065,10 +2062,6 @@ bool SILoadStoreOptimizer::promoteConstantOffsetToImm(
   unsigned AS = SIInstrInfo::isFLATGlobal(MI) ? AMDGPUAS::GLOBAL_ADDRESS
                                               : AMDGPUAS::FLAT_ADDRESS;
 
-  if (MI.mayLoad() &&
-      TII->getNamedOperand(MI, AMDGPU::OpName::vdata) != nullptr)
-    return false;
-
   if (AnchorList.count(&MI))
     return false;
 
diff --git a/llvm/test/CodeGen/AMDGPU/promote-constOffset-to-imm.mir b/llvm/test/CodeGen/AMDGPU/promote-constOffset-to-imm.mir
index 4ecce2842455b..16a4a5147da71 100644
--- a/llvm/test/CodeGen/AMDGPU/promote-constOffset-to-imm.mir
+++ b/llvm/test/CodeGen/AMDGPU/promote-constOffset-to-imm.mir
@@ -282,3 +282,58 @@ body:             |
     %13:vreg_64 = REG_SEQUENCE %9, %subreg.sub0, %11, %subreg.sub1
     FLAT_STORE_DWORD %13, %0.sub1, 0, 0, implicit $exec, implicit $flat_scr
 ...
+
+---
+# GCN-LABEL: name: diffoporder_add_global_atomic_cmpswap
+# GFX9: GLOBAL_ATOMIC_CMPSWAP %{{[0-9]+}}, %0, 1000, 0,
+# GFX9: GLOBAL_ATOMIC_CMPSWAP %{{[0-9]+}}, %0, 0, 0,
+
+# GFX8: GLOBAL_ATOMIC_CMPSWAP %{{[0-9]+}}, %0, 0, 0,
+# GFX8: GLOBAL_ATOMIC_CMPSWAP %{{[0-9]+}}, %0, 0, 0,
+
+name: diffoporder_add_global_atomic_cmpswap
+body:             |
+  bb.0.entry:
+
+    %0:vreg_64 = COPY $vgpr0_vgpr1
+
+    %1:sgpr_32 = S_MOV_B32 4000
+    %2:vgpr_32, %3:sreg_64_xexec = V_ADD_CO_U32_e64 %0.sub0, %1, 0, implicit $exec
+    %4:vgpr_32, dead %5:sreg_64_xexec = V_ADDC_U32_e64 %0.sub1, 0, %3, 0, implicit $exec
+    %6:vreg_64 = REG_SEQUENCE %2, %subreg.sub0, %4, %subreg.sub1
+    GLOBAL_ATOMIC_CMPSWAP %6:vreg_64, %0:vreg_64, 0, 0, implicit $exec
+
+    %8:sgpr_32 = S_MOV_B32 3000
+    %9:vgpr_32, %10:sreg_64_xexec = V_ADD_CO_U32_e64 %0.sub0, %8, 0, implicit $exec
+    %11:vgpr_32, dead %12:sreg_64_xexec = V_ADDC_U32_e64 %0.sub1, 0, %10, 0, implicit $exec
+    %13:vreg_64 = REG_SEQUENCE %9, %subreg.sub0, %11, %subreg.sub1
+    GLOBAL_ATOMIC_CMPSWAP %13:vreg_64, %0:vreg_64, 0, 0, implicit $exec
+...
+
+---
+# GCN-LABEL: name: diffoporder_add_flat_atomic_cmpswap
+# GFX9: FLAT_ATOMIC_CMPSWAP %{{[0-9]+}}, %0, 1000, 0,
+# GFX9: FLAT_ATOMIC_CMPSWAP %{{[0-9]+}}, %0, 0, 0,
+
+# GFX8: FLAT_ATOMIC_CMPSWAP %{{[0-9]+}}, %0, 0, 0,
+# GFX8: FLAT_ATOMIC_CMPSWAP %{{[0-9]+}}, %0, 0, 0,
+
+name: diffoporder_add_flat_atomic_cmpswap
+body:             |
+  bb.0.entry:
+
+    %0:vreg_64 = COPY $vgpr0_vgpr1
+
+    %1:sgpr_32 = S_MOV_B32 4000
+    %2:vgpr_32, %3:sreg_64_xexec = V_ADD_CO_U32_e64 %0.sub0, %1, 0, implicit $exec
+    %4:vgpr_32, dead %5:sreg_64_xexec = V_ADDC_U32_e64 %0.sub1, 0, %3, 0, implicit $exec
+    %6:vreg_64 = REG_SEQUENCE %2, %subreg.sub0, %4, %subreg.sub1
+    FLAT_ATOMIC_CMPSWAP %6:vreg_64, %0:vreg_64, 0, 0, implicit $exec, implicit $flat_scr
+
+
+    %8:sgpr_32 = S_MOV_B32 3000
+    %9:vgpr_32, %10:sreg_64_xexec = V_ADD_CO_U32_e64 %0.sub0, %8, 0, implicit $exec
+    %11:vgpr_32, dead %12:sreg_64_xexec = V_ADDC_U32_e64 %0.sub1, 0, %10, 0, implicit $exec
+    %13:vreg_64 = REG_SEQUENCE %9, %subreg.sub0, %11, %subreg.sub1
+    FLAT_ATOMIC_CMPSWAP %13:vreg_64, %0:vreg_64, 0, 0, implicit $exec, implicit $flat_scr
+...

``````````

</details>


https://github.com/llvm/llvm-project/pull/94043