[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).

1 files changed, 6 insertions, 14 deletions

diff --git a/clang/lib/CodeGen/CGExpr.cpp b/clang/lib/CodeGen/CGExpr.cpp
index ed35a055d8a7..f1affef756df 100644
--- a/clang/lib/CodeGen/CGExpr.cpp
+++ b/clang/lib/CodeGen/CGExpr.cpp
@@ -588,11 +588,9 @@ EmitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *M) {
   } else {
     switch (M->getStorageDuration()) {
     case SD_Automatic:
-      if (auto *Size = EmitLifetimeStart(
-              CGM.getDataLayout().getTypeAllocSize(Alloca.getElementType()),
-              Alloca.getPointer())) {
+      if (EmitLifetimeStart(Alloca.getPointer())) {
         pushCleanupAfterFullExpr<CallLifetimeEnd>(NormalEHLifetimeMarker,
-                                                  Alloca, Size);
+                                                  Alloca);
       }
       break;
 
@@ -623,11 +621,8 @@ EmitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *M) {
             Block, llvm::BasicBlock::iterator(Block->back())));
       }
 
-      if (auto *Size = EmitLifetimeStart(
-              CGM.getDataLayout().getTypeAllocSize(Alloca.getElementType()),
-              Alloca.getPointer())) {
-        pushFullExprCleanup<CallLifetimeEnd>(NormalEHLifetimeMarker, Alloca,
-                                             Size);
+      if (EmitLifetimeStart(Alloca.getPointer())) {
+        pushFullExprCleanup<CallLifetimeEnd>(NormalEHLifetimeMarker, Alloca);
       }
 
       if (OldConditional) {
@@ -5784,13 +5779,10 @@ LValue CodeGenFunction::EmitHLSLOutArgExpr(const HLSLOutArgExpr *E,
   llvm::Value *Addr = TempLV.getAddress().getBasePointer();
   llvm::Type *ElTy = ConvertTypeForMem(TempLV.getType());
 
-  llvm::TypeSize Sz = CGM.getDataLayout().getTypeAllocSize(ElTy);
-
-  llvm::Value *LifetimeSize = EmitLifetimeStart(Sz, Addr);
+  EmitLifetimeStart(Addr);
 
   Address TmpAddr(Addr, ElTy, TempLV.getAlignment());
-  Args.addWriteback(BaseLV, TmpAddr, nullptr, E->getWritebackCast(),
-                    LifetimeSize);
+  Args.addWriteback(BaseLV, TmpAddr, nullptr, E->getWritebackCast());
   Args.add(RValue::get(TmpAddr, *this), Ty);
   return TempLV;
 }