[PATCH] D94155: [X86] Fix tile config register spill issue.

[Pengfei Wang via Phabricator via llvm-commits]

pengfei added inline comments.


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Comment at: llvm/include/llvm/CodeGen/LiveIntervals.h:384
+    bool getInterferenceRegMasks(LiveInterval &LI,
+                                 SmallVector<SlotIndex, 8> &RegSlots,
+                                 SmallVector<const uint32_t *, 8> &RegMaskBits);
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Seems we usually use `SmallVectorImpl<...>` here.


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Comment at: llvm/lib/CodeGen/LiveIntervals.cpp:956
+bool LiveIntervals::getInterferenceRegMasks(
+    LiveInterval &LI, SmallVector<SlotIndex, 8> &RegSlots,
+    SmallVector<const uint32_t *, 8> &RegBits) {
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The same here.


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Comment at: llvm/lib/CodeGen/LiveIntervals.cpp:982
+
+  bool Found = false;
+  while (true) {
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Should `Found` always be `true` in our case?


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Comment at: llvm/test/CodeGen/X86/AMX/amx-across-func.ll:109
   %4 = tail call x86_amx @llvm.x86.tileloadd64.internal(i16 8, i16 %1, i8* getelementptr inbounds ([3072 x i8], [3072 x i8]* @buf, i64 0, i64 1024), i64 32)
-  tail call void (...) @foo()
+  call void @foo()
   %5 = tail call x86_amx @llvm.x86.tileloadd64.internal(i16 %0, i16 %1, i8* getelementptr inbounds ([3072 x i8], [3072 x i8]* @buf, i64 0, i64 2048), i64 32)
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How about if it is a tail call?


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Comment at: llvm/test/CodeGen/X86/AMX/amx-across-func.ll:113
   tail call void @llvm.x86.tilestored64.internal(i16 %0, i16 %1, i8* getelementptr inbounds ([3072 x i8], [3072 x i8]* @buf, i64 0, i64 2048), i64 32, x86_amx %6)
   ret void
 }
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It's better to add another foo after all users of tmm registers to make sure no `ldtilecfg` been generated.


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Comment at: llvm/test/CodeGen/X86/AMX/amx-spill-merge.ll:110
 ; CHECK-NEXT:    retq
   %c = tail call x86_amx @llvm.x86.tileloadd64.internal(i16 %0, i16 %1, i8* getelementptr inbounds ([3072 x i8], [3072 x i8]* @buf, i64 0, i64 2048), i64 32)
   br i1 undef, label %if.true, label %if.false
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It's better add a call before any user of tmm instructions to see if ldtilecfg can be sunk


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D94155/new/

https://reviews.llvm.org/D94155