AMDGPU: Process SDWA block at a time

Right now this loops over the entire function every time there
is a change, which is not very efficient. There's no practical
reason to track this so globally, since the code motion optimization
passes should be sinking instructions with single uses and
the pass currently will not fold with multiple uses.

llvm-svn: 324667

1 files changed, 31 insertions, 32 deletions

diff --git a/llvm/lib/Target/AMDGPU/SIPeepholeSDWA.cpp b/llvm/lib/Target/AMDGPU/SIPeepholeSDWA.cpp
index 6f332fd5b33..cf7676b46b1 100644
--- a/llvm/lib/Target/AMDGPU/SIPeepholeSDWA.cpp
+++ b/llvm/lib/Target/AMDGPU/SIPeepholeSDWA.cpp
@@ -86,7 +86,7 @@ public:
   }
 
   bool runOnMachineFunction(MachineFunction &MF) override;
-  void matchSDWAOperands(MachineFunction &MF);
+  void matchSDWAOperands(MachineBasicBlock &MBB);
   std::unique_ptr<SDWAOperand> matchSDWAOperand(MachineInstr &MI);
   bool isConvertibleToSDWA(const MachineInstr &MI, const SISubtarget &ST) const;
   bool convertToSDWA(MachineInstr &MI, const SDWAOperandsVector &SDWAOperands);
@@ -804,14 +804,12 @@ SIPeepholeSDWA::matchSDWAOperand(MachineInstr &MI) {
   return std::unique_ptr<SDWAOperand>(nullptr);
 }
 
-void SIPeepholeSDWA::matchSDWAOperands(MachineFunction &MF) {
-  for (MachineBasicBlock &MBB : MF) {
-    for (MachineInstr &MI : MBB) {
-      if (auto Operand = matchSDWAOperand(MI)) {
-        DEBUG(dbgs() << "Match: " << MI << "To: " << *Operand << '\n');
-        SDWAOperands[&MI] = std::move(Operand);
-        ++NumSDWAPatternsFound;
-      }
+void SIPeepholeSDWA::matchSDWAOperands(MachineBasicBlock &MBB) {
+  for (MachineInstr &MI : MBB) {
+    if (auto Operand = matchSDWAOperand(MI)) {
+      DEBUG(dbgs() << "Match: " << MI << "To: " << *Operand << '\n');
+      SDWAOperands[&MI] = std::move(Operand);
+      ++NumSDWAPatternsFound;
     }
   }
 }
@@ -1059,35 +1057,36 @@ bool SIPeepholeSDWA::runOnMachineFunction(MachineFunction &MF) {
   TII = ST.getInstrInfo();
 
   // Find all SDWA operands in MF.
-  bool Changed = false;
   bool Ret = false;
-  do {
-    matchSDWAOperands(MF);
-
-    for (const auto &OperandPair : SDWAOperands) {
-      const auto &Operand = OperandPair.second;
-      MachineInstr *PotentialMI = Operand->potentialToConvert(TII);
-      if (PotentialMI && isConvertibleToSDWA(*PotentialMI, ST)) {
-        PotentialMatches[PotentialMI].push_back(Operand.get());
+  for (MachineBasicBlock &MBB : MF) {
+    bool Changed = false;
+    do {
+      matchSDWAOperands(MBB);
+
+      for (const auto &OperandPair : SDWAOperands) {
+        const auto &Operand = OperandPair.second;
+        MachineInstr *PotentialMI = Operand->potentialToConvert(TII);
+        if (PotentialMI && isConvertibleToSDWA(*PotentialMI, ST)) {
+          PotentialMatches[PotentialMI].push_back(Operand.get());
+        }
       }
-    }
 
-    for (auto &PotentialPair : PotentialMatches) {
-      MachineInstr &PotentialMI = *PotentialPair.first;
-      convertToSDWA(PotentialMI, PotentialPair.second);
-    }
-
-    PotentialMatches.clear();
-    SDWAOperands.clear();
+      for (auto &PotentialPair : PotentialMatches) {
+        MachineInstr &PotentialMI = *PotentialPair.first;
+        convertToSDWA(PotentialMI, PotentialPair.second);
+      }
 
-    Changed = !ConvertedInstructions.empty();
+      PotentialMatches.clear();
+      SDWAOperands.clear();
 
-    if (Changed)
-      Ret = true;
+      Changed = !ConvertedInstructions.empty();
 
-    while (!ConvertedInstructions.empty())
-      legalizeScalarOperands(*ConvertedInstructions.pop_back_val(), ST);
-  } while (Changed);
+      if (Changed)
+        Ret = true;
+      while (!ConvertedInstructions.empty())
+        legalizeScalarOperands(*ConvertedInstructions.pop_back_val(), ST);
+    } while (Changed);
+  }
 
   return Ret;
 }