Remove O0-exclusivity, use enum-typed arg, address minor comments

Author: SLTozer

clang/lib/CodeGen/CGDecl.cpp

@@ -1353,11 +1353,6 @@ void CodeGenFunction::EmitLifetimeEnd(llvm::Value *Size, llvm::Value *Addr) {
 }
 
 void CodeGenFunction::EmitFakeUse(Address Addr) {
-  // We do not emit a fake use if we want to apply optnone to this function,
-  // even if we might not apply it anyway due to minsize or similar attributes.
-  if (!CGM.getCodeGenOpts().DisableO0ImplyOptNone &&
-      CGM.getCodeGenOpts().OptimizationLevel == 0)
-    return;
   auto NL = ApplyDebugLocation::CreateEmpty(*this);
   llvm::Value *V = Builder.CreateLoad(Addr, "fake.use");
   llvm::CallInst *C = Builder.CreateCall(CGM.getLLVMFakeUseFn(), {V});
@@ -1432,9 +1427,9 @@ static uint64_t maxFakeUseAggregateSize(const ASTContext &C) {
 
 // Helper function to determine whether a variable's or parameter's lifetime
 // should be extended.
-static bool extendLifetime(const ASTContext &Context, const Decl *FuncDecl,
-                           const VarDecl &D,
-                           ImplicitParamDecl *CXXABIThisDecl) {
+static bool shouldExtendLifetime(const ASTContext &Context,
+                                 const Decl *FuncDecl, const VarDecl &D,
+                                 ImplicitParamDecl *CXXABIThisDecl) {
   // When we're not inside a valid function it is unlikely that any
   // lifetime extension is useful.
   if (!FuncDecl)
@@ -1711,13 +1706,14 @@ CodeGenFunction::EmitAutoVarAlloca(const VarDecl &D) {
 
   // Analogous to lifetime markers, we use a 'cleanup' to emit fake.use
   // calls for local variables. We are exempting volatile variables and
-  // non-scalars larger than 4 times the size of an unsigned int (32 bytes).
-  // Larger non-scalars are often allocated in memory and may create unnecessary
+  // non-scalars larger than 4 times the size of an unsigned int. Larger
+  // non-scalars are often allocated in memory and may create unnecessary
   // overhead.
-  if (CGM.getCodeGenOpts().ExtendLifetimes) {
-    if (extendLifetime(getContext(), CurCodeDecl, D, CXXABIThisDecl))
+  if (CGM.getCodeGenOpts().getExtendVariableLiveness() ==
+      CodeGenOptions::ExtendVariableLivenessKind::All) {
+    if (shouldExtendLifetime(getContext(), CurCodeDecl, D, CXXABIThisDecl))
       EHStack.pushCleanup<FakeUse>(NormalFakeUse,
-                                   emission.getOriginalAllocatedAddress());
+                                   emission.getAllocatedAddress());
   }
 
   return emission;
@@ -2785,9 +2781,12 @@ void CodeGenFunction::EmitParmDecl(const VarDecl &D, ParamValue Arg,
   // Push a FakeUse 'cleanup' object onto the EHStack for the parameter,
   // which may be the 'this' pointer. This causes the emission of a fake.use
   // call with the parameter as argument at the end of the function.
-  if (CGM.getCodeGenOpts().ExtendLifetimes ||
-      (CGM.getCodeGenOpts().ExtendThisPtr && &D == CXXABIThisDecl)) {
-    if (extendLifetime(getContext(), CurCodeDecl, D, CXXABIThisDecl))
+  if (CGM.getCodeGenOpts().getExtendVariableLiveness() ==
+          CodeGenOptions::ExtendVariableLivenessKind::All ||
+      (CGM.getCodeGenOpts().getExtendVariableLiveness() ==
+           CodeGenOptions::ExtendVariableLivenessKind::This &&
+       &D == CXXABIThisDecl)) {
+    if (shouldExtendLifetime(getContext(), CurCodeDecl, D, CXXABIThisDecl))
       EHStack.pushCleanup<FakeUse>(NormalFakeUse, DeclPtr);
   }
 

clang/lib/Frontend/CompilerInvocation.cpp

@@ -1834,13 +1834,6 @@ bool CompilerInvocation::ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args,
     Opts.setInlining(CodeGenOptions::NormalInlining);
   }
 
-  // Extended lifetimes are meaningless if we are not going to run any
-  // optimizations, so skip them here.
-  if (Opts.OptimizationLevel == 0 && !Opts.DisableO0ImplyOptNone) {
-    Opts.ExtendLifetimes = false;
-    Opts.ExtendThisPtr = false;
-  }
-
   // PIC defaults to -fno-direct-access-external-data while non-PIC defaults to
   // -fdirect-access-external-data.
   Opts.DirectAccessExternalData =

clang/test/CodeGen/extend-liveness-except.cpp renamed to clang/test/CodeGen/extend-variable-liveness-except.cpp

@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 %s -O0 -disable-O0-optnone -emit-llvm -fextend-lifetimes -fcxx-exceptions -fexceptions -o - | FileCheck %s
+// RUN: %clang_cc1 %s -emit-llvm -fextend-variable-liveness -fcxx-exceptions -fexceptions -o - | FileCheck %s
 // This test checks that the fake uses can be generated in exception handling
 // blocks and that we can emit fake uses for the __int128 data type.
 

clang/test/CodeGen/extend-liveness-wide-scalar.cpp renamed to clang/test/CodeGen/extend-variable-liveness-wide-scalar.cpp

@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 %s -disable-O0-optnone -emit-llvm -fextend-lifetimes -triple x86_64-unknown-linux -o - | FileCheck %s
+// RUN: %clang_cc1 %s -emit-llvm -fextend-variable-liveness -triple x86_64-unknown-linux -o - | FileCheck %s
 // REQUIRES: x86-registered-target
 // This test checks that the fake uses can be generated in exception handling
 // blocks and that we can emit fake uses for the __int128 data type.

clang/test/CodeGen/extend-liveness1.c renamed to clang/test/CodeGen/extend-variable-liveness.c

@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 %s -O0 -disable-O0-optnone -emit-llvm -fextend-lifetimes -o - | FileCheck %s --implicit-check-not=llvm.fake.use
+// RUN: %clang_cc1 %s -emit-llvm -fextend-variable-liveness -o - | FileCheck %s --implicit-check-not=llvm.fake.use
 // Check that fake use calls are emitted at the correct locations, i.e.
 // at the end of lexical blocks and at the end of the function.
 

clang/test/CodeGen/fake-use-determinism.c

@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -O0 -disable-O0-optnone -emit-llvm -fextend-lifetimes %s -o - | FileCheck %s
+// RUN: %clang_cc1 -emit-llvm -fextend-variable-liveness %s -o - | FileCheck %s
 //
 // We are checking that the fake.use calls for i, j and k appear
 // in a particular order. It is not the order itself that is important

clang/test/CodeGen/fake-use-lambda.cpp

@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 %s -triple=%itanium_abi_triple -O1 -emit-llvm -fextend-lifetimes -o - | FileCheck %s
+// RUN: %clang_cc1 %s -triple=%itanium_abi_triple -O1 -emit-llvm -fextend-variable-liveness -o - | FileCheck %s
 // Make sure we don't crash compiling a lambda that is not nested in a function.
 // We also check that fake uses are properly issued in lambdas.
 

clang/test/CodeGen/fake-use-landingpad.c

@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 %s -O0 -disable-O0-optnone -emit-llvm -fextend-lifetimes -fexceptions -o - | FileCheck %s --implicit-check-not="landingpad {"
+// RUN: %clang_cc1 %s -emit-llvm -fextend-variable-liveness -fexceptions -o - | FileCheck %s --implicit-check-not="landingpad {"
 
 // Check that fake uses do not mistakenly cause a landing pad to be generated when
 // exceptions are enabled.

clang/test/CodeGen/fake-use-noreturn.cpp

@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 %s -emit-llvm -fextend-lifetimes -O0 -disable-O0-optnone -o - | FileCheck %s
+// RUN: %clang_cc1 %s -emit-llvm -fextend-variable-liveness -o - | FileCheck %s
 //
 // Check we can correctly produce fake uses for function-level variables even
 // when we have a return in a nested conditional and there is no code at the end

clang/test/CodeGen/fake-use-return-line.c

@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -emit-llvm -O0 -disable-O0-optnone -debug-info-kind=limited -fextend-lifetimes -o - %s | FileCheck %s
+// RUN: %clang_cc1 -emit-llvm -debug-info-kind=limited -fextend-variable-liveness -o - %s | FileCheck %s
 
 // Clang adjusts the line numbers of returns based on the line numbers of
 // dominating stores to %retval; we test that fake use intrinsics do not affect