RuntimeLibcalls: Add entries for stack probe functions

arsenm · arsenm · commit 5b6205700386 · 2025-11-11T15:08:38.000-08:00
Stop hardcoding different variants of __chkstk and query the
name through RuntimeLibcalls.
diff --git a/llvm/include/llvm/IR/RuntimeLibcalls.td b/llvm/include/llvm/IR/RuntimeLibcalls.td
@@ -406,6 +406,7 @@ def STACK_SMASH_HANDLER : RuntimeLibcall;
 // Safe stack
 def SAFESTACK_POINTER_ADDRESS : RuntimeLibcall;
 
+def STACK_PROBE : RuntimeLibcall;
 def SECURITY_CHECK_COOKIE : RuntimeLibcall;
 
 // Deoptimization
@@ -1084,6 +1085,15 @@ def __stack_smash_handler : RuntimeLibcallImpl<STACK_SMASH_HANDLER>;
 
 def __riscv_flush_icache : RuntimeLibcallImpl<RISCV_FLUSH_ICACHE>;
 
+def _chkstk : RuntimeLibcallImpl<STACK_PROBE>;
+def _alloca : RuntimeLibcallImpl<STACK_PROBE>;
+
+def __chkstk : RuntimeLibcallImpl<STACK_PROBE>;
+def ___chkstk_ms : RuntimeLibcallImpl<STACK_PROBE>;
+
+def __chkstk_ms : RuntimeLibcallImpl<STACK_PROBE>;
+def __chkstk_arm64ec : RuntimeLibcallImpl<STACK_PROBE, "#__chkstk_arm64ec">;
+
 def __security_check_cookie : RuntimeLibcallImpl<SECURITY_CHECK_COOKIE>;
 def __security_check_cookie_arm64ec : RuntimeLibcallImpl<SECURITY_CHECK_COOKIE,
   "#__security_check_cookie_arm64ec">;
@@ -1260,6 +1270,9 @@ defvar SecurityCheckCookieIfWinMSVC =
     LibcallImpls<(add __security_check_cookie, __security_cookie),
                  isWindowsMSVCOrItaniumEnvironment>;
 
+defvar __chkstk_IfWinMSVC =
+    LibcallImpls<(add __chkstk), isWindowsMSVCEnvironment>;
+
 defvar LibmHasSinCosF32 = LibcallImpls<(add sincosf), hasSinCos>;
 defvar LibmHasSinCosF64 =  LibcallImpls<(add sincos), hasSinCos>;
 defvar LibmHasSinCosF80 = LibcallImpls<(add sincosl_f80), hasSinCos>;
@@ -1418,6 +1431,7 @@ def AArch64SystemLibrary : SystemRuntimeLibrary<
        DefaultLibmExp10,
        DefaultStackProtector,
        SecurityCheckCookieIfWinMSVC,
+       __chkstk_IfWinMSVC,
        SMEABI_LibCalls_PreserveMost_From_X0,
        SMEABI_LibCalls_PreserveMost_From_X1,
        SMEABI_LibCalls_PreserveMost_From_X2)
@@ -1465,6 +1479,7 @@ def WindowsARM64ECSystemLibrary
                                 LibcallImpls<(add __security_check_cookie_arm64ec,
                                                   __security_cookie),
                                               isWindowsMSVCEnvironment>,
+                                __chkstk_arm64ec,
                                 ExceptionModelCallsArm64EC)>;
 
 //===----------------------------------------------------------------------===//
@@ -1882,6 +1897,7 @@ def ARMSystemLibrary
            WindowARMDivRemCalls,
            WindowARMFPIntCasts,
            SecurityCheckCookieIfWinMSVC,
+           LibcallImpls<(add __chkstk), isOSWindows>,
            AEABIDivRemCalls,
            DarwinSinCosStret, DarwinExp10,
            LibmHasSinCosF32, LibmHasSinCosF64, LibmHasSinCosF128,
@@ -2552,6 +2568,19 @@ def isX86_32 : RuntimeLibcallPredicate<"TT.getArch() == Triple::x86">;
 def isX86_64 : RuntimeLibcallPredicate<"TT.getArch() == Triple::x86_64">;
 def isX86 : RuntimeLibcallPredicate<"TT.isX86()">;
 
+def isCygwinMinGW64 : RuntimeLibcallPredicate<
+  [{TT.isOSCygMing() && TT.getArch() == Triple::x86_64}]>;
+def isCygwinMinGW32 : RuntimeLibcallPredicate<
+  [{TT.isOSCygMing() && TT.getArch() == Triple::x86}]>;
+
+def isWin32NotCygMing : RuntimeLibcallPredicate<
+  [{TT.getArch() == Triple::x86 &&
+     (TT.isOSWindows() || TT.isUEFI()) && !TT.isOSCygMing()}]>;
+def isWin64NotCygMing : RuntimeLibcallPredicate<
+  [{TT.getArch() == Triple::x86_64 &&
+    (TT.isOSWindows() || TT.isUEFI()) && !TT.isOSCygMing()}]>;
+
+
 // Some darwins have an optimized __bzero/bzero function.
 def darwinHas__bzero : RuntimeLibcallPredicate<"TT.isMacOSX() && !TT.isMacOSXVersionLT(10, 6)">;
 
@@ -2581,8 +2610,12 @@ defvar X86CommonLibcalls =
        // FIXME: MSVCRT doesn't have powi. The f128 case is added as a
        // hack for one test relying on it.
        __powitf2_f128,
-       DefaultStackProtector
-     );
+       DefaultStackProtector,
+       LibcallImpls<(add ___chkstk_ms), isCygwinMinGW64>,
+       LibcallImpls<(add __chkstk), isWin64NotCygMing>,
+       LibcallImpls<(add _alloca), isCygwinMinGW32>,
+       LibcallImpls<(add _chkstk), isWin32NotCygMing>
+);
 
 defvar Windows32DivRemMulCalls =
   LibcallsWithCC<(add WindowsDivRemMulLibcalls), X86_STDCALL,
diff --git a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
@@ -16857,11 +16857,15 @@ AArch64TargetLowering::LowerWindowsDYNAMIC_STACKALLOC(SDValue Op,
     return DAG.getMergeValues(Ops, DL);
   }
 
+  RTLIB::LibcallImpl ChkStkImpl = getLibcallImpl(RTLIB::STACK_PROBE);
+  if (ChkStkImpl == RTLIB::Unsupported)
+    return SDValue();
+
   Chain = DAG.getCALLSEQ_START(Chain, 0, 0, DL);
 
   EVT PtrVT = getPointerTy(DAG.getDataLayout());
-  SDValue Callee = DAG.getTargetExternalSymbol(Subtarget->getChkStkName(),
-                                               PtrVT, 0);
+  SDValue Callee = DAG.getTargetExternalSymbol(
+      getLibcallImplName(ChkStkImpl).data(), PtrVT, 0);
 
   const AArch64RegisterInfo *TRI = Subtarget->getRegisterInfo();
   const uint32_t *Mask = TRI->getWindowsStackProbePreservedMask();
diff --git a/llvm/lib/Target/AArch64/AArch64PrologueEpilogue.cpp b/llvm/lib/Target/AArch64/AArch64PrologueEpilogue.cpp
@@ -1135,7 +1135,12 @@ void AArch64PrologueEmitter::emitWindowsStackProbe(
         .setMIFlags(MachineInstr::FrameSetup);
   }
 
-  const char *ChkStk = Subtarget.getChkStkName();
+  const AArch64TargetLowering *TLI = Subtarget.getTargetLowering();
+  RTLIB::LibcallImpl ChkStkLibcall = TLI->getLibcallImpl(RTLIB::STACK_PROBE);
+  if (ChkStkLibcall == RTLIB::Unsupported)
+    reportFatalUsageError("no available implementation of __chkstk");
+
+  const char *ChkStk = TLI->getLibcallImplName(ChkStkLibcall).data();
   switch (MF.getTarget().getCodeModel()) {
   case CodeModel::Tiny:
   case CodeModel::Small:
diff --git a/llvm/lib/Target/AArch64/AArch64Subtarget.h b/llvm/lib/Target/AArch64/AArch64Subtarget.h
@@ -450,12 +450,6 @@ class AArch64Subtarget final : public AArch64GenSubtargetInfo {
   /// add + cnt instructions.
   bool useScalarIncVL() const;
 
-  const char* getChkStkName() const {
-    if (isWindowsArm64EC())
-      return "#__chkstk_arm64ec";
-    return "__chkstk";
-  }
-
   /// Choose a method of checking LR before performing a tail call.
   AArch64PAuth::AuthCheckMethod
   getAuthenticatedLRCheckMethod(const MachineFunction &MF) const;
diff --git a/llvm/lib/Target/ARM/ARMFrameLowering.cpp b/llvm/lib/Target/ARM/ARMFrameLowering.cpp
@@ -1138,6 +1138,12 @@ void ARMFrameLowering::emitPrologue(MachineFunction &MF,
           .add(predOps(ARMCC::AL));
     }
 
+    const ARMTargetLowering *TLI = STI.getTargetLowering();
+    RTLIB::LibcallImpl ChkStkLibcall = TLI->getLibcallImpl(RTLIB::STACK_PROBE);
+    if (ChkStkLibcall == RTLIB::Unsupported)
+      reportFatalUsageError("no available implementation of __chkstk");
+    const char *ChkStk = TLI->getLibcallImplName(ChkStkLibcall).data();
+
     switch (TM.getCodeModel()) {
     case CodeModel::Tiny:
       llvm_unreachable("Tiny code model not available on ARM.");
@@ -1146,14 +1152,14 @@ void ARMFrameLowering::emitPrologue(MachineFunction &MF,
     case CodeModel::Kernel:
       BuildMI(MBB, MBBI, dl, TII.get(ARM::tBL))
           .add(predOps(ARMCC::AL))
-          .addExternalSymbol("__chkstk")
+          .addExternalSymbol(ChkStk)
           .addReg(ARM::R4, RegState::Implicit)
           .setMIFlags(MachineInstr::FrameSetup);
       break;
     case CodeModel::Large:
       BuildMI(MBB, MBBI, dl, TII.get(ARM::t2MOVi32imm), ARM::R12)
-        .addExternalSymbol("__chkstk")
-        .setMIFlags(MachineInstr::FrameSetup);
+          .addExternalSymbol(ChkStk)
+          .setMIFlags(MachineInstr::FrameSetup);
 
       BuildMI(MBB, MBBI, dl, TII.get(ARM::tBLXr))
           .add(predOps(ARMCC::AL))
diff --git a/llvm/lib/Target/ARM/ARMISelLowering.cpp b/llvm/lib/Target/ARM/ARMISelLowering.cpp
@@ -11727,6 +11727,11 @@ ARMTargetLowering::EmitLowered__chkstk(MachineInstr &MI,
   // -mcmodel=large, alleviating the need for the trampoline which may clobber
   // IP.
 
+  RTLIB::LibcallImpl ChkStkLibcall = getLibcallImpl(RTLIB::STACK_PROBE);
+  if (ChkStkLibcall == RTLIB::Unsupported)
+    reportFatalUsageError("no available implementation of __chkstk");
+
+  const char *ChkStk = getLibcallImplName(ChkStkLibcall).data();
   switch (TM.getCodeModel()) {
   case CodeModel::Tiny:
     llvm_unreachable("Tiny code model not available on ARM.");
@@ -11735,7 +11740,7 @@ ARMTargetLowering::EmitLowered__chkstk(MachineInstr &MI,
   case CodeModel::Kernel:
     BuildMI(*MBB, MI, DL, TII.get(ARM::tBL))
         .add(predOps(ARMCC::AL))
-        .addExternalSymbol("__chkstk")
+        .addExternalSymbol(ChkStk)
         .addReg(ARM::R4, RegState::Implicit | RegState::Kill)
         .addReg(ARM::R4, RegState::Implicit | RegState::Define)
         .addReg(ARM::R12,
@@ -11748,7 +11753,7 @@ ARMTargetLowering::EmitLowered__chkstk(MachineInstr &MI,
     Register Reg = MRI.createVirtualRegister(&ARM::rGPRRegClass);
 
     BuildMI(*MBB, MI, DL, TII.get(ARM::t2MOVi32imm), Reg)
-      .addExternalSymbol("__chkstk");
+        .addExternalSymbol(ChkStk);
     BuildMI(*MBB, MI, DL, TII.get(gettBLXrOpcode(*MBB->getParent())))
         .add(predOps(ARMCC::AL))
         .addReg(Reg, RegState::Kill)
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -62436,9 +62436,10 @@ X86TargetLowering::getStackProbeSymbolName(const MachineFunction &MF) const {
 
   // We need a stack probe to conform to the Windows ABI. Choose the right
   // symbol.
-  if (Subtarget.is64Bit())
-    return Subtarget.isTargetCygMing() ? "___chkstk_ms" : "__chkstk";
-  return Subtarget.isTargetCygMing() ? "_alloca" : "_chkstk";
+  RTLIB::LibcallImpl StackProbeImpl = getLibcallImpl(RTLIB::STACK_PROBE);
+  if (StackProbeImpl == RTLIB::Unsupported)
+    return "";
+  return getLibcallImplName(StackProbeImpl);
 }
 
 unsigned
