[llvm] 92f1f1e - [Coroutines] Use to collect lifetime marker of in CoroFrame Differential Revision: https://reviews.llvm.org/D85279

Chuanqi Xu via llvm-commits llvm-commits at lists.llvm.org
Wed Aug 5 23:22:14 PDT 2020


Author: Chuanqi Xu
Date: 2020-08-06T14:21:55+08:00
New Revision: 92f1f1e40d4c99c36754a9e527f071d80c276770

URL: https://github.com/llvm/llvm-project/commit/92f1f1e40d4c99c36754a9e527f071d80c276770
DIFF: https://github.com/llvm/llvm-project/commit/92f1f1e40d4c99c36754a9e527f071d80c276770.diff

LOG: [Coroutines] Use  to collect lifetime marker of  in CoroFrame Differential Revision: https://reviews.llvm.org/D85279

Added: 
    llvm/test/Transforms/Coroutines/coro-split-sink-lifetime-03.ll
    llvm/test/Transforms/Coroutines/coro-split-sink-lifetime-04.ll

Modified: 
    llvm/lib/Transforms/Coroutines/CoroFrame.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Transforms/Coroutines/CoroFrame.cpp b/llvm/lib/Transforms/Coroutines/CoroFrame.cpp
index f55501a05d85..b2677b4572e4 100644
--- a/llvm/lib/Transforms/Coroutines/CoroFrame.cpp
+++ b/llvm/lib/Transforms/Coroutines/CoroFrame.cpp
@@ -1567,50 +1567,70 @@ static void sinkLifetimeStartMarkers(Function &F, coro::Shape &Shape,
   }
 
   for (Instruction &I : instructions(F)) {
-    if (!isa<AllocaInst>(&I))
+    AllocaInst* AI = dyn_cast<AllocaInst>(&I);
+    if (!AI)
       continue;
 
     for (BasicBlock *DomBB : DomSet) {
       bool Valid = true;
-      SmallVector<Instruction *, 1> BCInsts;
+      SmallVector<Instruction *, 1> Lifetimes;
 
-      auto isUsedByLifetimeStart = [&](Instruction *I) {
-        if (isa<BitCastInst>(I) && I->hasOneUse())
-          if (auto *IT = dyn_cast<IntrinsicInst>(I->user_back()))
-            return IT->getIntrinsicID() == Intrinsic::lifetime_start;
+      auto isLifetimeStart = [](Instruction* I) {
+        if (auto* II = dyn_cast<IntrinsicInst>(I))
+          return II->getIntrinsicID() == Intrinsic::lifetime_start;
         return false;
       };
 
-      for (User *U : I.users()) {
+      auto collectLifetimeStart = [&](Instruction *U, AllocaInst *AI) {
+        if (isLifetimeStart(U)) {
+          Lifetimes.push_back(U);
+          return true;
+        }
+        if (!U->hasOneUse() || U->stripPointerCasts() != AI)
+          return false;
+        if (isLifetimeStart(U->user_back())) {
+          Lifetimes.push_back(U->user_back());
+          return true;
+        }
+        return false;
+      };
+
+      for (User *U : AI->users()) {
         Instruction *UI = cast<Instruction>(U);
         // For all users except lifetime.start markers, if they are all
         // dominated by one of the basic blocks and do not cross
         // suspend points as well, then there is no need to spill the
         // instruction.
         if (!DT.dominates(DomBB, UI->getParent()) ||
-            Checker.isDefinitionAcrossSuspend(DomBB, U)) {
-          // Skip bitcast used by lifetime.start markers.
-          if (isUsedByLifetimeStart(UI)) {
-            BCInsts.push_back(UI);
+            Checker.isDefinitionAcrossSuspend(DomBB, UI)) {
+          // Skip lifetime.start, GEP and bitcast used by lifetime.start
+          // markers.
+          if (collectLifetimeStart(UI, AI))
             continue;
-          }
           Valid = false;
           break;
         }
       }
       // Sink lifetime.start markers to dominate block when they are
       // only used outside the region.
-      if (Valid && BCInsts.size() != 0) {
-        auto *NewBitcast = BCInsts[0]->clone();
-        auto *NewLifetime = cast<Instruction>(BCInsts[0]->user_back())->clone();
-        NewLifetime->replaceUsesOfWith(BCInsts[0], NewBitcast);
-        NewBitcast->insertBefore(DomBB->getTerminator());
+      if (Valid && Lifetimes.size() != 0) {
+        // May be AI itself, when the type of AI is i8*
+        auto *NewBitCast = [&](AllocaInst *AI) -> Value* {
+          if (isa<AllocaInst>(Lifetimes[0]->getOperand(1)))
+            return AI;
+          auto *Int8PtrTy = Type::getInt8PtrTy(F.getContext());
+          return CastInst::Create(Instruction::BitCast, AI, Int8PtrTy, "",
+                                  DomBB->getTerminator());
+        }(AI);
+
+        auto *NewLifetime = Lifetimes[0]->clone();
+        NewLifetime->replaceUsesOfWith(NewLifetime->getOperand(1), NewBitCast);
         NewLifetime->insertBefore(DomBB->getTerminator());
 
         // All the outsided lifetime.start markers are no longer necessary.
-        for (Instruction *S : BCInsts) {
-          S->user_back()->eraseFromParent();
-        }
+        for (Instruction *S : Lifetimes)
+          S->eraseFromParent();
+
         break;
       }
     }
@@ -1676,14 +1696,14 @@ void coro::buildCoroutineFrame(Function &F, Shape &Shape) {
     if (!II || II->getIntrinsicID() != Intrinsic::lifetime_start)
       continue;
 
-    if (auto *OpInst = dyn_cast<BitCastInst>(I.getOperand(1)))
-      if (auto *AI = dyn_cast<AllocaInst>(OpInst->getOperand(0))) {
+    if (auto *OpInst = dyn_cast<Instruction>(II->getOperand(1))) {
+      if (auto *AI = dyn_cast<AllocaInst>(OpInst->stripPointerCasts())) {
 
         if (LifetimeMap.find(AI) == LifetimeMap.end())
           LifetimeMap[AI] = std::make_unique<LifetimeStart>();
-
-        LifetimeMap[AI]->insert(OpInst);
+        LifetimeMap[AI]->insert(isa<AllocaInst>(OpInst) ? II : OpInst);
       }
+    }
   }
 
   // Collect the spills for arguments and other not-materializable values.

diff  --git a/llvm/test/Transforms/Coroutines/coro-split-sink-lifetime-03.ll b/llvm/test/Transforms/Coroutines/coro-split-sink-lifetime-03.ll
new file mode 100644
index 000000000000..6d27959f98b0
--- /dev/null
+++ b/llvm/test/Transforms/Coroutines/coro-split-sink-lifetime-03.ll
@@ -0,0 +1,71 @@
+; Corresponding to coro-split-sink-lifetime-01.ll. This file tests that whether the CoroFrame
+; pass knows the operand of lifetime.start intrinsic may be GEP as well.
+; RUN: opt < %s -coro-split -S | FileCheck %s
+; RUN: opt < %s -passes=coro-split -S | FileCheck %s
+
+%"struct.std::coroutine_handle" = type { i8* }
+%"struct.std::coroutine_handle.0" = type { %"struct.std::coroutine_handle" }
+%"struct.lean_future<int>::Awaiter" = type { i32, %"struct.std::coroutine_handle.0" }
+
+declare i8* @malloc(i64)
+declare void @print(i32)
+
+%i8.array = type { [100 x i8] }
+declare void @consume.i8.array(%i8.array*)
+
+define void @a.gep() "coroutine.presplit"="1" {
+entry:
+  %ref.tmp7 = alloca %"struct.lean_future<int>::Awaiter", align 8
+  %testval = alloca %i8.array
+  %cast = getelementptr inbounds %i8.array, %i8.array* %testval, i64 0, i32 0, i64 0
+  ; lifetime of %testval starts here, but not used until await.ready.
+  call void @llvm.lifetime.start.p0i8(i64 100, i8* %cast)
+  %id = call token @llvm.coro.id(i32 0, i8* null, i8* null, i8* null)
+  %alloc = call i8* @malloc(i64 16) #3
+  %vFrame = call noalias nonnull i8* @llvm.coro.begin(token %id, i8* %alloc)
+
+  %save = call token @llvm.coro.save(i8* null)
+  %Result.i19 = getelementptr inbounds %"struct.lean_future<int>::Awaiter", %"struct.lean_future<int>::Awaiter"* %ref.tmp7, i64 0, i32 0
+  %suspend = call i8 @llvm.coro.suspend(token %save, i1 false)
+  switch i8 %suspend, label %exit [
+    i8 0, label %await.ready
+    i8 1, label %exit
+  ]
+await.ready:
+  %StrayCoroSave = call token @llvm.coro.save(i8* null)
+  %val = load i32, i32* %Result.i19
+  call void @consume.i8.array(%i8.array* %testval)
+  call void @llvm.lifetime.end.p0i8(i64 100, i8*  %cast)
+  call void @print(i32 %val)
+  br label %exit
+exit:
+  call i1 @llvm.coro.end(i8* null, i1 false)
+  ret void
+}
+; CHECK-LABEL: @a.gep.resume(
+; CHECK:         %testval = alloca %i8.array
+; CHECK-NEXT:    %0 = bitcast %i8.array* %testval to i8*
+; CHECK-NEXT:    call void @llvm.lifetime.start.p0i8(i64 100, i8* %0)
+; CHECK-NEXT:    getelementptr inbounds %a.gep.Frame
+; CHECK-NEXT:    getelementptr inbounds %"struct.lean_future<int>::Awaiter"
+; CHECK-NEXT:    getelementptr inbounds %i8.array, %i8.array* %testval
+; CHECK-NEXT:    %val = load i32, i32* %Result
+; CHECK-NEXT:    call void @consume.i8.array(%i8.array* %testval)
+; CHECK-NEXT:    call void @llvm.lifetime.end.p0i8(i64 100, i8* %cast1)
+; CHECK-NEXT:    call void @print(i32 %val)
+; CHECK-NEXT:    ret void
+
+declare token @llvm.coro.id(i32, i8* readnone, i8* nocapture readonly, i8*)
+declare i1 @llvm.coro.alloc(token) #3
+declare noalias nonnull i8* @"\01??2 at YAPEAX_K@Z"(i64) local_unnamed_addr
+declare i64 @llvm.coro.size.i64() #5
+declare i8* @llvm.coro.begin(token, i8* writeonly) #3
+declare void @"\01?puts@@YAXZZ"(...)
+declare token @llvm.coro.save(i8*) #3
+declare i8* @llvm.coro.frame() #5
+declare i8 @llvm.coro.suspend(token, i1) #3
+declare void @"\01??3 at YAXPEAX@Z"(i8*) local_unnamed_addr #10
+declare i8* @llvm.coro.free(token, i8* nocapture readonly) #2
+declare i1 @llvm.coro.end(i8*, i1) #3
+declare void @llvm.lifetime.start.p0i8(i64, i8* nocapture) #4
+declare void @llvm.lifetime.end.p0i8(i64, i8* nocapture) #4

diff  --git a/llvm/test/Transforms/Coroutines/coro-split-sink-lifetime-04.ll b/llvm/test/Transforms/Coroutines/coro-split-sink-lifetime-04.ll
new file mode 100644
index 000000000000..0d06c0d486db
--- /dev/null
+++ b/llvm/test/Transforms/Coroutines/coro-split-sink-lifetime-04.ll
@@ -0,0 +1,70 @@
+; Tests that coro-split will optimize the lifetime.start maker of each local variable,
+; sink them to the places after the suspend block.
+; RUN: opt < %s -coro-split -S | FileCheck %s
+; RUN: opt < %s -passes=coro-split -S | FileCheck %s
+
+%"struct.std::coroutine_handle" = type { i8* }
+%"struct.std::coroutine_handle.0" = type { %"struct.std::coroutine_handle" }
+%"struct.lean_future<int>::Awaiter" = type { i32, %"struct.std::coroutine_handle.0" }
+
+declare i8* @malloc(i64)
+declare void @print(i32)
+declare void @consume.i8(i8)
+
+define void @a() "coroutine.presplit"="1" {
+entry:
+  %ref.tmp7 = alloca %"struct.lean_future<int>::Awaiter", align 8
+  %testval = alloca i8
+  ; lifetime of %testval starts here, but not used until await.ready.
+  call void @llvm.lifetime.start.p0i8(i64 1, i8* %testval)
+  %id = call token @llvm.coro.id(i32 0, i8* null, i8* null, i8* null)
+  %alloc = call i8* @malloc(i64 16) #3
+  %vFrame = call noalias nonnull i8* @llvm.coro.begin(token %id, i8* %alloc)
+
+  %save = call token @llvm.coro.save(i8* null)
+  %Result.i19 = getelementptr inbounds %"struct.lean_future<int>::Awaiter", %"struct.lean_future<int>::Awaiter"* %ref.tmp7, i64 0, i32 0
+  %suspend = call i8 @llvm.coro.suspend(token %save, i1 false)
+  switch i8 %suspend, label %exit [
+    i8 0, label %await.ready
+    i8 1, label %exit
+  ]
+await.ready:
+  %StrayCoroSave = call token @llvm.coro.save(i8* null)
+  %val = load i32, i32* %Result.i19
+  %test = load i8, i8* %testval
+  call void @consume.i8(i8 %test)
+  call void @llvm.lifetime.end.p0i8(i64 1, i8* %testval)
+  call void @print(i32 %val)
+  br label %exit
+exit:
+  call i1 @llvm.coro.end(i8* null, i1 false)
+  ret void
+}
+
+; CHECK-LABEL: @a.resume(
+; CHECK:         %testval = alloca i8, align 1
+; CHECK-NEXT:    call void @llvm.lifetime.start.p0i8(i64 1, i8* %testval)
+; CHECK-NEXT:    getelementptr inbounds %a.Frame
+; CHECK-NEXT:    getelementptr inbounds %"struct.lean_future<int>::Awaiter"
+; CHECK-NEXT:    %val = load i32, i32* %Result
+; CHECK-NEXT:    %test = load i8, i8* %testval
+; CHECK-NEXT:    call void @consume.i8(i8 %test)
+; CHECK-NEXT:    call void @llvm.lifetime.end.p0i8(i64 1, i8* %testval)
+; CHECK-NEXT:    call void @print(i32 %val)
+; CHECK-NEXT:    ret void
+
+
+declare token @llvm.coro.id(i32, i8* readnone, i8* nocapture readonly, i8*)
+declare i1 @llvm.coro.alloc(token) #3
+declare noalias nonnull i8* @"\01??2 at YAPEAX_K@Z"(i64) local_unnamed_addr
+declare i64 @llvm.coro.size.i64() #5
+declare i8* @llvm.coro.begin(token, i8* writeonly) #3
+declare void @"\01?puts@@YAXZZ"(...)
+declare token @llvm.coro.save(i8*) #3
+declare i8* @llvm.coro.frame() #5
+declare i8 @llvm.coro.suspend(token, i1) #3
+declare void @"\01??3 at YAXPEAX@Z"(i8*) local_unnamed_addr #10
+declare i8* @llvm.coro.free(token, i8* nocapture readonly) #2
+declare i1 @llvm.coro.end(i8*, i1) #3
+declare void @llvm.lifetime.start.p0i8(i64, i8* nocapture) #4
+declare void @llvm.lifetime.end.p0i8(i64, i8* nocapture) #4


        


More information about the llvm-commits mailing list