[IR] Remove size argument from lifetime intrinsics (#150248)

Now that #149310 has restricted lifetime intrinsics to only work on
allocas, we can also drop the explicit size argument. Instead, the size
is implied by the alloca.

This removes the ability to only mark a prefix of an alloca alive/dead.
We never used that capability, so we should remove the need to handle
that possibility everywhere (though many key places, including stack
coloring, did not actually respect this).

3 files changed, 8 insertions, 9 deletions

diff --git a/llvm/lib/CodeGen/AtomicExpandPass.cpp b/llvm/lib/CodeGen/AtomicExpandPass.cpp
index 3f3d5dc9..278dd65 100644
--- a/llvm/lib/CodeGen/AtomicExpandPass.cpp
+++ b/llvm/lib/CodeGen/AtomicExpandPass.cpp
@@ -1915,7 +1915,6 @@ bool AtomicExpandImpl::expandAtomicOpToLibcall(
 
   // TODO: the "order" argument type is "int", not int32. So
   // getInt32Ty may be wrong if the arch uses e.g. 16-bit ints.
-  ConstantInt *SizeVal64 = ConstantInt::get(Type::getInt64Ty(Ctx), Size);
   assert(Ordering != AtomicOrdering::NotAtomic && "expect atomic MO");
   Constant *OrderingVal =
       ConstantInt::get(Type::getInt32Ty(Ctx), (int)toCABI(Ordering));
@@ -2012,7 +2011,7 @@ bool AtomicExpandImpl::expandAtomicOpToLibcall(
   if (CASExpected) {
     AllocaCASExpected = AllocaBuilder.CreateAlloca(CASExpected->getType());
     AllocaCASExpected->setAlignment(AllocaAlignment);
-    Builder.CreateLifetimeStart(AllocaCASExpected, SizeVal64);
+    Builder.CreateLifetimeStart(AllocaCASExpected);
     Builder.CreateAlignedStore(CASExpected, AllocaCASExpected, AllocaAlignment);
     Args.push_back(AllocaCASExpected);
   }
@@ -2026,7 +2025,7 @@ bool AtomicExpandImpl::expandAtomicOpToLibcall(
     } else {
       AllocaValue = AllocaBuilder.CreateAlloca(ValueOperand->getType());
       AllocaValue->setAlignment(AllocaAlignment);
-      Builder.CreateLifetimeStart(AllocaValue, SizeVal64);
+      Builder.CreateLifetimeStart(AllocaValue);
       Builder.CreateAlignedStore(ValueOperand, AllocaValue, AllocaAlignment);
       Args.push_back(AllocaValue);
     }
@@ -2036,7 +2035,7 @@ bool AtomicExpandImpl::expandAtomicOpToLibcall(
   if (!CASExpected && HasResult && !UseSizedLibcall) {
     AllocaResult = AllocaBuilder.CreateAlloca(I->getType());
     AllocaResult->setAlignment(AllocaAlignment);
-    Builder.CreateLifetimeStart(AllocaResult, SizeVal64);
+    Builder.CreateLifetimeStart(AllocaResult);
     Args.push_back(AllocaResult);
   }
 
@@ -2069,7 +2068,7 @@ bool AtomicExpandImpl::expandAtomicOpToLibcall(
 
   // And then, extract the results...
   if (ValueOperand && !UseSizedLibcall)
-    Builder.CreateLifetimeEnd(AllocaValue, SizeVal64);
+    Builder.CreateLifetimeEnd(AllocaValue);
 
   if (CASExpected) {
     // The final result from the CAS is {load of 'expected' alloca, bool result
@@ -2078,7 +2077,7 @@ bool AtomicExpandImpl::expandAtomicOpToLibcall(
     Value *V = PoisonValue::get(FinalResultTy);
     Value *ExpectedOut = Builder.CreateAlignedLoad(
         CASExpected->getType(), AllocaCASExpected, AllocaAlignment);
-    Builder.CreateLifetimeEnd(AllocaCASExpected, SizeVal64);
+    Builder.CreateLifetimeEnd(AllocaCASExpected);
     V = Builder.CreateInsertValue(V, ExpectedOut, 0);
     V = Builder.CreateInsertValue(V, Result, 1);
     I->replaceAllUsesWith(V);
@@ -2089,7 +2088,7 @@ bool AtomicExpandImpl::expandAtomicOpToLibcall(
     else {
       V = Builder.CreateAlignedLoad(I->getType(), AllocaResult,
                                     AllocaAlignment);
-      Builder.CreateLifetimeEnd(AllocaResult, SizeVal64);
+      Builder.CreateLifetimeEnd(AllocaResult);
     }
     I->replaceAllUsesWith(V);
   }
diff --git a/llvm/lib/CodeGen/GlobalISel/IRTranslator.cpp b/llvm/lib/CodeGen/GlobalISel/IRTranslator.cpp
index bbfae57..d30dfa7 100644
--- a/llvm/lib/CodeGen/GlobalISel/IRTranslator.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/IRTranslator.cpp
@@ -2209,7 +2209,7 @@ bool IRTranslator::translateKnownIntrinsic(const CallInst &CI, Intrinsic::ID ID,
     unsigned Op = ID == Intrinsic::lifetime_start ? TargetOpcode::LIFETIME_START
                                                   : TargetOpcode::LIFETIME_END;
 
-    const AllocaInst *AI = dyn_cast<AllocaInst>(CI.getArgOperand(1));
+    const AllocaInst *AI = dyn_cast<AllocaInst>(CI.getArgOperand(0));
     if (!AI || !AI->isStaticAlloca())
       return true;
 
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index f5f5c14..0d1e954 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -7597,7 +7597,7 @@ void SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I,
     if (TM.getOptLevel() == CodeGenOptLevel::None)
       return;
 
-    const AllocaInst *LifetimeObject = dyn_cast<AllocaInst>(I.getArgOperand(1));
+    const AllocaInst *LifetimeObject = dyn_cast<AllocaInst>(I.getArgOperand(0));
     if (!LifetimeObject)
       return;