[llvm] d7938b1 - MachineModuleInfo: Move HasSplitStack handling to AsmPrinter
Matt Arsenault via llvm-commits
llvm-commits at lists.llvm.org
Wed Apr 20 07:54:34 PDT 2022
Author: Matt Arsenault
Date: 2022-04-20T10:54:29-04:00
New Revision: d7938b1a817006388f95de5ea2ee74daa7cde892
URL: https://github.com/llvm/llvm-project/commit/d7938b1a817006388f95de5ea2ee74daa7cde892
DIFF: https://github.com/llvm/llvm-project/commit/d7938b1a817006388f95de5ea2ee74daa7cde892.diff
LOG: MachineModuleInfo: Move HasSplitStack handling to AsmPrinter
This is used to emit one field in doFinalization for the module. We
can accumulate this when emitting all individual functions directly in
the AsmPrinter, rather than accumulating additional state in
MachineModuleInfo.
Move the special case behavior predicate into MachineFrameInfo to
share it. This now promotes it to generic behavior. I'm assuming this
is fine because no other target implements adjustForSegmentedStacks,
or has tests using the split-stack attribute.
Added:
Modified:
llvm/include/llvm/CodeGen/AsmPrinter.h
llvm/include/llvm/CodeGen/MachineFrameInfo.h
llvm/include/llvm/CodeGen/MachineModuleInfo.h
llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
llvm/lib/CodeGen/MachineModuleInfo.cpp
llvm/lib/CodeGen/PrologEpilogInserter.cpp
llvm/lib/Target/ARM/ARMAsmPrinter.cpp
llvm/lib/Target/ARM/ARMFrameLowering.cpp
llvm/lib/Target/X86/X86FrameLowering.cpp
Removed:
################################################################################
diff --git a/llvm/include/llvm/CodeGen/AsmPrinter.h b/llvm/include/llvm/CodeGen/AsmPrinter.h
index c6f300ac5bebf..99c1918ff1d08 100644
--- a/llvm/include/llvm/CodeGen/AsmPrinter.h
+++ b/llvm/include/llvm/CodeGen/AsmPrinter.h
@@ -210,6 +210,16 @@ class AsmPrinter : public MachineFunctionPass {
/// CFISection type the module needs i.e. either .eh_frame or .debug_frame.
CFISection ModuleCFISection = CFISection::None;
+ /// True if the module contains split-stack functions. This is used to
+ /// emit .note.GNU-split-stack section as required by the linker for
+ /// special handling split-stack function calling no-split-stack function.
+ bool HasSplitStack = false;
+
+ /// True if the module contains no-split-stack functions. This is used to emit
+ /// .note.GNU-no-split-stack section when it also contains functions without a
+ /// split stack prologue.
+ bool HasNoSplitStack = false;
+
protected:
explicit AsmPrinter(TargetMachine &TM, std::unique_ptr<MCStreamer> Streamer);
diff --git a/llvm/include/llvm/CodeGen/MachineFrameInfo.h b/llvm/include/llvm/CodeGen/MachineFrameInfo.h
index edf4d9b89434a..2d018aa73fec1 100644
--- a/llvm/include/llvm/CodeGen/MachineFrameInfo.h
+++ b/llvm/include/llvm/CodeGen/MachineFrameInfo.h
@@ -385,6 +385,20 @@ class MachineFrameInfo {
bool hasPatchPoint() const { return HasPatchPoint; }
void setHasPatchPoint(bool s = true) { HasPatchPoint = s; }
+ /// Return true if this function requires a split stack prolog, even if it
+ /// uses no stack space. This is only meaningful for functions where
+ /// MachineFunction::shouldSplitStack() returns true.
+ //
+ // For non-leaf functions we have to allow for the possibility that the call
+ // is to a non-split function, as in PR37807. This function could also take
+ // the address of a non-split function. When the linker tries to adjust its
+ // non-existent prologue, it would fail with an error. Mark the object file so
+ // that such failures are not errors. See this Go language bug-report
+ // https://go-review.googlesource.com/c/go/+/148819/
+ bool needsSplitStackProlog() const {
+ return getStackSize() != 0 || hasTailCall();
+ }
+
/// Return the minimum frame object index.
int getObjectIndexBegin() const { return -NumFixedObjects; }
diff --git a/llvm/include/llvm/CodeGen/MachineModuleInfo.h b/llvm/include/llvm/CodeGen/MachineModuleInfo.h
index 4eaae9f1ed7f7..88951266dc3a0 100644
--- a/llvm/include/llvm/CodeGen/MachineModuleInfo.h
+++ b/llvm/include/llvm/CodeGen/MachineModuleInfo.h
@@ -129,16 +129,6 @@ class MachineModuleInfo {
/// comments in lib/Target/X86/X86FrameLowering.cpp for more details.
bool UsesMorestackAddr;
- /// True if the module contains split-stack functions. This is used to
- /// emit .note.GNU-split-stack section as required by the linker for
- /// special handling split-stack function calling no-split-stack function.
- bool HasSplitStack;
-
- /// True if the module contains no-split-stack functions. This is used to
- /// emit .note.GNU-no-split-stack section when it also contains split-stack
- /// functions.
- bool HasNosplitStack;
-
/// Maps IR Functions to their corresponding MachineFunctions.
DenseMap<const Function*, std::unique_ptr<MachineFunction>> MachineFunctions;
/// Next unique number available for a MachineFunction.
@@ -213,22 +203,6 @@ class MachineModuleInfo {
UsesMorestackAddr = b;
}
- bool hasSplitStack() const {
- return HasSplitStack;
- }
-
- void setHasSplitStack(bool b) {
- HasSplitStack = b;
- }
-
- bool hasNosplitStack() const {
- return HasNosplitStack;
- }
-
- void setHasNosplitStack(bool b) {
- HasNosplitStack = b;
- }
-
/// Return the symbol to be used for the specified basic block when its
/// address is taken. This cannot be its normal LBB label because the block
/// may be accessed outside its containing function.
diff --git a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index b89cc46af486a..5e697be9581ba 100644
--- a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -257,6 +257,8 @@ void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
bool AsmPrinter::doInitialization(Module &M) {
auto *MMIWP = getAnalysisIfAvailable<MachineModuleInfoWrapperPass>();
MMI = MMIWP ? &MMIWP->getMMI() : nullptr;
+ HasSplitStack = false;
+ HasNoSplitStack = false;
// Initialize TargetLoweringObjectFile.
const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
@@ -1921,10 +1923,10 @@ bool AsmPrinter::doFinalization(Module &M) {
// Emit .note.GNU-split-stack and .note.GNU-no-split-stack sections if
// split-stack is used.
- if (TM.getTargetTriple().isOSBinFormatELF() && MMI->hasSplitStack()) {
+ if (TM.getTargetTriple().isOSBinFormatELF() && HasSplitStack) {
OutStreamer->SwitchSection(
OutContext.getELFSection(".note.GNU-split-stack", ELF::SHT_PROGBITS, 0));
- if (MMI->hasNosplitStack())
+ if (HasNoSplitStack)
OutStreamer->SwitchSection(
OutContext.getELFSection(".note.GNU-no-split-stack", ELF::SHT_PROGBITS, 0));
}
@@ -1991,6 +1993,16 @@ void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
this->MF = &MF;
const Function &F = MF.getFunction();
+ // Record that there are split-stack functions, so we will emit a special
+ // section to tell the linker.
+ if (MF.shouldSplitStack()) {
+ HasSplitStack = true;
+
+ if (!MF.getFrameInfo().needsSplitStackProlog())
+ HasNoSplitStack = true;
+ } else
+ HasNoSplitStack = true;
+
// Get the function symbol.
if (!MAI->needsFunctionDescriptors()) {
CurrentFnSym = getSymbol(&MF.getFunction());
diff --git a/llvm/lib/CodeGen/MachineModuleInfo.cpp b/llvm/lib/CodeGen/MachineModuleInfo.cpp
index 4ee24272ef5a2..1e1b9e9c08a20 100644
--- a/llvm/lib/CodeGen/MachineModuleInfo.cpp
+++ b/llvm/lib/CodeGen/MachineModuleInfo.cpp
@@ -203,7 +203,6 @@ void MachineModuleInfo::initialize() {
CurCallSite = 0;
NextFnNum = 0;
UsesMSVCFloatingPoint = UsesMorestackAddr = false;
- HasSplitStack = HasNosplitStack = false;
AddrLabelSymbols = nullptr;
DbgInfoAvailable = false;
}
@@ -232,8 +231,6 @@ MachineModuleInfo::MachineModuleInfo(MachineModuleInfo &&MMI)
CurCallSite = MMI.CurCallSite;
UsesMSVCFloatingPoint = MMI.UsesMSVCFloatingPoint;
UsesMorestackAddr = MMI.UsesMorestackAddr;
- HasSplitStack = MMI.HasSplitStack;
- HasNosplitStack = MMI.HasNosplitStack;
AddrLabelSymbols = MMI.AddrLabelSymbols;
ExternalContext = MMI.ExternalContext;
TheModule = MMI.TheModule;
diff --git a/llvm/lib/CodeGen/PrologEpilogInserter.cpp b/llvm/lib/CodeGen/PrologEpilogInserter.cpp
index 6e0c867d4efcc..ee22cbd5af14b 100644
--- a/llvm/lib/CodeGen/PrologEpilogInserter.cpp
+++ b/llvm/lib/CodeGen/PrologEpilogInserter.cpp
@@ -1144,11 +1144,7 @@ void PEI::insertPrologEpilogCode(MachineFunction &MF) {
if (MF.shouldSplitStack()) {
for (MachineBasicBlock *SaveBlock : SaveBlocks)
TFI.adjustForSegmentedStacks(MF, *SaveBlock);
- // Record that there are split-stack functions, so we will emit a
- // special section to tell the linker.
- MF.getMMI().setHasSplitStack(true);
- } else
- MF.getMMI().setHasNosplitStack(true);
+ }
// Emit additional code that is required to explicitly handle the stack in
// HiPE native code (if needed) when loaded in the Erlang/OTP runtime. The
diff --git a/llvm/lib/Target/ARM/ARMAsmPrinter.cpp b/llvm/lib/Target/ARM/ARMAsmPrinter.cpp
index 0874bae7d4614..5f35a0013c60e 100644
--- a/llvm/lib/Target/ARM/ARMAsmPrinter.cpp
+++ b/llvm/lib/Target/ARM/ARMAsmPrinter.cpp
@@ -24,6 +24,7 @@
#include "llvm/ADT/SetVector.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/BinaryFormat/COFF.h"
+#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineJumpTableInfo.h"
#include "llvm/CodeGen/MachineModuleInfoImpls.h"
diff --git a/llvm/lib/Target/ARM/ARMFrameLowering.cpp b/llvm/lib/Target/ARM/ARMFrameLowering.cpp
index b9b417865691f..c2cc3024aca9e 100644
--- a/llvm/lib/Target/ARM/ARMFrameLowering.cpp
+++ b/llvm/lib/Target/ARM/ARMFrameLowering.cpp
@@ -2506,19 +2506,10 @@ void ARMFrameLowering::adjustForSegmentedStacks(
ARMFunctionInfo *ARMFI = MF.getInfo<ARMFunctionInfo>();
DebugLoc DL;
- uint64_t StackSize = MFI.getStackSize();
-
- // Do not generate a prologue for leaf functions with a stack of size zero.
- // For non-leaf functions we have to allow for the possibility that the
- // callis to a non-split function, as in PR37807. This function could also
- // take the address of a non-split function. When the linker tries to adjust
- // its non-existent prologue, it would fail with an error. Mark the object
- // file so that such failures are not errors. See this Go language bug-report
- // https://go-review.googlesource.com/c/go/+/148819/
- if (StackSize == 0 && !MFI.hasTailCall()) {
- MF.getMMI().setHasNosplitStack(true);
+ if (!MFI.needsSplitStackProlog())
return;
- }
+
+ uint64_t StackSize = MFI.getStackSize();
// Use R4 and R5 as scratch registers.
// We save R4 and R5 before use and restore them before leaving the function.
diff --git a/llvm/lib/Target/X86/X86FrameLowering.cpp b/llvm/lib/Target/X86/X86FrameLowering.cpp
index fe72f79e25320..1086e0ac72d0e 100644
--- a/llvm/lib/Target/X86/X86FrameLowering.cpp
+++ b/llvm/lib/Target/X86/X86FrameLowering.cpp
@@ -2944,17 +2944,8 @@ void X86FrameLowering::adjustForSegmentedStacks(
// prologue.
StackSize = MFI.getStackSize();
- // Do not generate a prologue for leaf functions with a stack of size zero.
- // For non-leaf functions we have to allow for the possibility that the
- // callis to a non-split function, as in PR37807. This function could also
- // take the address of a non-split function. When the linker tries to adjust
- // its non-existent prologue, it would fail with an error. Mark the object
- // file so that such failures are not errors. See this Go language bug-report
- // https://go-review.googlesource.com/c/go/+/148819/
- if (StackSize == 0 && !MFI.hasTailCall()) {
- MF.getMMI().setHasNosplitStack(true);
+ if (!MFI.needsSplitStackProlog())
return;
- }
MachineBasicBlock *allocMBB = MF.CreateMachineBasicBlock();
MachineBasicBlock *checkMBB = MF.CreateMachineBasicBlock();
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