[llvm] [Mips] Fix mfhi/mflo hazard miscompilation about div and mult (PR #91449)

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git-clang-format --diff ef0291e5f4451abbafab0c839bf51a6382f735f3 225aaca1d703a027d868b4049c3572a659fb78c3 -- llvm/lib/Target/Mips/Mips.h llvm/lib/Target/Mips/MipsBranchExpansion.cpp llvm/lib/Target/Mips/MipsDelaySlotFiller.cpp llvm/lib/Target/Mips/MipsInstrInfo.cpp llvm/lib/Target/Mips/MipsInstrInfo.h
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View the diff from clang-format here.
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``````````diff
diff --git a/llvm/lib/Target/Mips/Mips.h b/llvm/lib/Target/Mips/Mips.h
index 673143c0a0..32df648f21 100644
--- a/llvm/lib/Target/Mips/Mips.h
+++ b/llvm/lib/Target/Mips/Mips.h
@@ -17,14 +17,16 @@
 #include "MCTargetDesc/MipsMCTargetDesc.h"
 #include "llvm/Target/TargetMachine.h"
 
-#define IsMFLOMFHI(instr) (instr == Mips::MFLO || instr == Mips::MFLO64 || \
-                           instr == Mips::MFHI || instr ==  Mips::MFHI64)
-#define IsDIVMULT(instr) (instr == Mips::SDIV || instr == Mips::PseudoSDIV || \
-                  instr == Mips::DSDIV || instr == Mips::PseudoDSDIV || \
-                  instr == Mips::UDIV || instr == Mips::PseudoUDIV || \
-                  instr == Mips::DUDIV || instr == Mips::PseudoDUDIV || \
-                  instr == Mips::MULT || instr == Mips::PseudoMULT || \
-                  instr == Mips::DMULT || instr == Mips::PseudoDMULT)
+#define IsMFLOMFHI(instr)                                                      \
+  (instr == Mips::MFLO || instr == Mips::MFLO64 || instr == Mips::MFHI ||      \
+   instr == Mips::MFHI64)
+#define IsDIVMULT(instr)                                                       \
+  (instr == Mips::SDIV || instr == Mips::PseudoSDIV || instr == Mips::DSDIV || \
+   instr == Mips::PseudoDSDIV || instr == Mips::UDIV ||                        \
+   instr == Mips::PseudoUDIV || instr == Mips::DUDIV ||                        \
+   instr == Mips::PseudoDUDIV || instr == Mips::MULT ||                        \
+   instr == Mips::PseudoMULT || instr == Mips::DMULT ||                        \
+   instr == Mips::PseudoDMULT)
 
 namespace llvm {
 class FunctionPass;
diff --git a/llvm/lib/Target/Mips/MipsBranchExpansion.cpp b/llvm/lib/Target/Mips/MipsBranchExpansion.cpp
index b632a9e4e1..a42fe39e40 100644
--- a/llvm/lib/Target/Mips/MipsBranchExpansion.cpp
+++ b/llvm/lib/Target/Mips/MipsBranchExpansion.cpp
@@ -769,23 +769,21 @@ bool MipsBranchExpansion::handleSlot(Pred Predicate, Safe SafeInSlot) {
         if (std::next(Iit) == FI->end() ||
             std::next(Iit)->getOpcode() != Mips::NOP) {
           Changed = true;
-	  if (Predicate(*I) ||
-             (!LastInstInFunction && !SafeInSlot(*IInSlot, *I))){
+          if (Predicate(*I) ||
+              (!LastInstInFunction && !SafeInSlot(*IInSlot, *I))) {
             TII->insertNop(*(I->getParent()), std::next(I), I->getDebugLoc())
                 ->bundleWithPred();
             NumInsertedNops++;
           }
-          if (IsMFLOMFHI(I->getOpcode()) &&
-              !LastInstInFunction &&
+          if (IsMFLOMFHI(I->getOpcode()) && !LastInstInFunction &&
               IsDIVMULT(IInSlot->getOpcode())) {
             TII->insertNop(*(I->getParent()), std::next(I), I->getDebugLoc())
                 ->bundleWithPred();
             NumInsertedNops++;
           }
         }
-      }
-      else if (IsMFLOMFHI(I->getOpcode())) {
-          hasPendingMFLO = true;
+      } else if (IsMFLOMFHI(I->getOpcode())) {
+        hasPendingMFLO = true;
       }
     }
   }
@@ -799,11 +797,10 @@ bool MipsBranchExpansion::handleMFLO() {
   if (STI->hasMips32() || STI->hasMips5())
     return false;
 
-  return handleSlot(
-      [this](auto &I) -> bool { return TII->IsMfloOrMfhi(I); },
-      [this](auto &IInSlot, auto &I) -> bool {
-        return TII->SafeAfterMflo(IInSlot);
-      });
+  return handleSlot([this](auto &I) -> bool { return TII->IsMfloOrMfhi(I); },
+                    [this](auto &IInSlot, auto &I) -> bool {
+                      return TII->SafeAfterMflo(IInSlot);
+                    });
 }
 
 bool MipsBranchExpansion::handleForbiddenSlot() {
@@ -925,8 +922,7 @@ bool MipsBranchExpansion::runOnMachineFunction(MachineFunction &MF) {
   bool MfloChanged = handleMFLO();
 
   bool Changed = longBranchChanged || forbiddenSlotChanged ||
-                 fpuDelaySlotChanged || loadDelaySlotChanged ||
-                 MfloChanged;
+                 fpuDelaySlotChanged || loadDelaySlotChanged || MfloChanged;
 
   // Then run them alternatively while there are changes.
   while (forbiddenSlotChanged) {
@@ -934,8 +930,8 @@ bool MipsBranchExpansion::runOnMachineFunction(MachineFunction &MF) {
     fpuDelaySlotChanged = handleFPUDelaySlot();
     loadDelaySlotChanged = handleLoadDelaySlot();
     MfloChanged = handleMFLO();
-    if (!longBranchChanged && !fpuDelaySlotChanged &&
-	!loadDelaySlotChanged && !MfloChanged)
+    if (!longBranchChanged && !fpuDelaySlotChanged && !loadDelaySlotChanged &&
+        !MfloChanged)
       break;
     forbiddenSlotChanged = handleForbiddenSlot();
   }
diff --git a/llvm/lib/Target/Mips/MipsDelaySlotFiller.cpp b/llvm/lib/Target/Mips/MipsDelaySlotFiller.cpp
index d7e938bc05..e0401ba8d7 100644
--- a/llvm/lib/Target/Mips/MipsDelaySlotFiller.cpp
+++ b/llvm/lib/Target/Mips/MipsDelaySlotFiller.cpp
@@ -745,8 +745,8 @@ bool MipsDelaySlotFiller::searchRange(MachineBasicBlock &MBB, IterTy Begin,
     unsigned Opcode = (*Slot).getOpcode();
 
     if ((CurrI->getOpcode() == Mips::MFLO ||
-	 CurrI->getOpcode() == Mips::MFLO64) &&
-       (!STI.hasMips32() && !STI.hasMips5()))
+         CurrI->getOpcode() == Mips::MFLO64) &&
+        (!STI.hasMips32() && !STI.hasMips5()))
       continue;
 
     // This is complicated by the tail call optimization. For non-PIC code
diff --git a/llvm/lib/Target/Mips/MipsInstrInfo.cpp b/llvm/lib/Target/Mips/MipsInstrInfo.cpp
index 9a23f72372..663be430a2 100644
--- a/llvm/lib/Target/Mips/MipsInstrInfo.cpp
+++ b/llvm/lib/Target/Mips/MipsInstrInfo.cpp
@@ -11,9 +11,9 @@
 //===----------------------------------------------------------------------===//
 
 #include "MipsInstrInfo.h"
-#include "Mips.h"
 #include "MCTargetDesc/MipsBaseInfo.h"
 #include "MCTargetDesc/MipsMCTargetDesc.h"
+#include "Mips.h"
 #include "MipsSubtarget.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/CodeGen/MachineBasicBlock.h"

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https://github.com/llvm/llvm-project/pull/91449