Index: lib/CodeGen/TargetPassConfig.cpp =================================================================== --- lib/CodeGen/TargetPassConfig.cpp +++ lib/CodeGen/TargetPassConfig.cpp @@ -111,9 +111,17 @@ cl::desc("Verify generated machine code"), cl::init(false), cl::ZeroOrMore); -static cl::opt EnableMachineOutliner("enable-machine-outliner", - cl::Hidden, - cl::desc("Enable machine outliner")); +enum RunOutliner { AlwaysOutline, NeverOutline }; +// Enable or disable the MachineOutliner. +static cl::opt EnableMachineOutliner( + "enable-machine-outliner", cl::desc("Enable the machine outliner"), + cl::Hidden, cl::ValueOptional, cl::init(NeverOutline), + cl::values(clEnumValN(AlwaysOutline, "always", + "Run on all functions guaranteed to be beneficial " + "(pass -enable-linkonceodr-outlining for more)"), + clEnumValN(NeverOutline, "never", "Disable all outlining"), + // Sentinel value for unspecified option. + clEnumValN(AlwaysOutline, "", ""))); // Enable or disable FastISel. Both options are needed, because // FastISel is enabled by default with -fast, and we wish to be // able to enable or disable fast-isel independently from -O0. @@ -906,7 +914,7 @@ addPass(&XRayInstrumentationID, false); addPass(&PatchableFunctionID, false); - if (EnableMachineOutliner) + if (EnableMachineOutliner == AlwaysOutline) addPass(createMachineOutlinerPass()); // Add passes that directly emit MI after all other MI passes. Index: test/CodeGen/AArch64/machine-outliner-flags.ll =================================================================== --- /dev/null +++ test/CodeGen/AArch64/machine-outliner-flags.ll @@ -0,0 +1,30 @@ +; RUN: llc %s -debug-pass=Structure -verify-machineinstrs \ +; RUN: -enable-machine-outliner=always -mtriple arm64---- -o /dev/null 2>&1 \ +; RUN: | FileCheck %s -check-prefix=ALWAYS + +; RUN: llc %s -debug-pass=Structure -verify-machineinstrs \ +; RUN: -enable-machine-outliner -mtriple arm64---- -o /dev/null 2>&1 \ +; RUN: | FileCheck %s -check-prefix=ENABLE + +; RUN: llc %s -debug-pass=Structure -verify-machineinstrs \ +; RUN: -enable-machine-outliner=never -mtriple arm64---- -o /dev/null 2>&1 \ +; RUN: | FileCheck %s -check-prefix=NEVER + +; RUN: llc %s -debug-pass=Structure -verify-machineinstrs \ +; RUN: -mtriple arm64---- -o /dev/null 2>&1 \ +; RUN: | FileCheck %s -check-prefix=NOT-ADDED + +; Make sure that the outliner flags all work properly. If we specify +; -enable-machine-outliner with always or no argument, it should be added to the +; pass pipeline. If we specify it with never, or don't pass the flag, +; then we shouldn't add it. + +; ALWAYS: Machine Outliner +; ENABLE: Machine Outliner +; NEVER-NOT: Machine Outliner +; NOT-ADDED-NOT: Machine Outliner + +define void @foo() { + ret void; +} +