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Index: lib/Target/X86/X86ISelLowering.cpp
===================================================================
--- lib/Target/X86/X86ISelLowering.cpp 2014-04-11 23:04:44.000000000 +0200
+++ lib/Target/X86/X86ISelLowering.cpp (working copy)
@@ -15493,12 +15493,36 @@
// non-trivial part is impdef of ESP.
if (Subtarget->isTargetWin64()) {
+ const char *StackProbeSymbol =
+ Subtarget->isTargetCygMing() ? "___chkstk" : "__chkstk";
+
+ MachineInstrBuilder MIB;
+
+ if (getTargetMachine().getCodeModel() == CodeModel::Large) {
+ // For large code model we need to do indirect call to __chkstk.
+
+ // R11 will be used to contain the address of __chkstk.
+ // R11 is a volotiale register and assumed to be destoyed by the callee,
+ // so there is no need to save and restore it.
+ BuildMI(*BB, MI, DL, TII->get(X86::MOV64ri), X86::R11)
+ .addExternalSymbol(StackProbeSymbol);
+ // Create a call to __chkstk function which address contained in R11.
+ MIB = BuildMI(*BB, MI, DL, TII->get(X86::CALL64r))
+ .addReg(X86::R11, RegState::Kill);
+
+ } else {
+
+ // For non-large code model we can do direct call to __chkstk.
+
+ MIB = BuildMI(*BB, MI, DL, TII->get(X86::W64ALLOCA))
+ .addExternalSymbol(StackProbeSymbol);
+ }
+
if (Subtarget->isTargetCygMing()) {
// ___chkstk(Mingw64):
// Clobbers R10, R11, RAX and EFLAGS.
// Updates RSP.
- BuildMI(*BB, MI, DL, TII->get(X86::W64ALLOCA))
- .addExternalSymbol("___chkstk")
+ MIB
.addReg(X86::RAX, RegState::Implicit)
.addReg(X86::RSP, RegState::Implicit)
.addReg(X86::RAX, RegState::Define | RegState::Implicit)
@@ -15507,8 +15531,7 @@
} else {
// __chkstk(MSVCRT): does not update stack pointer.
// Clobbers R10, R11 and EFLAGS.
- BuildMI(*BB, MI, DL, TII->get(X86::W64ALLOCA))
- .addExternalSymbol("__chkstk")
+ MIB
.addReg(X86::RAX, RegState::Implicit)
.addReg(X86::EFLAGS, RegState::Define | RegState::Implicit);
// RAX has the offset to be subtracted from RSP.
Index: lib/Target/X86/X86FrameLowering.cpp
===================================================================
--- lib/Target/X86/X86FrameLowering.cpp 2013-10-24 01:37:01.000000000 +0200
+++ lib/Target/X86/X86FrameLowering.cpp (working copy)
@@ -635,25 +635,49 @@
.addReg(X86::EAX, RegState::Kill)
.setMIFlag(MachineInstr::FrameSetup);
}
+
+ MachineInstrBuilder MIB;
if (Is64Bit) {
+
// Handle the 64-bit Windows ABI case where we need to call __chkstk.
// Function prologue is responsible for adjusting the stack pointer.
BuildMI(MBB, MBBI, DL, TII.get(X86::MOV64ri), X86::RAX)
.addImm(NumBytes)
.setMIFlag(MachineInstr::FrameSetup);
+
+ if (TM.getCodeModel() == CodeModel::Large) {
+ // For large code model we need to do indirect call to __chkstk.
+
+
+ // R11 will be used to contain the address of __chkstk.
+ // R11 is a volotiale register and assumed to be destoyed by the callee,
+ // so there is no need to save and restore it.
+ BuildMI(MBB, MBBI, DL, TII.get(X86::MOV64ri), X86::R11)
+ .addExternalSymbol(StackProbeSymbol);
+ // Create a call to __chkstk function which address contained in R11.
+ MIB = BuildMI(MBB, MBBI, DL, TII.get(X86::CALL64r))
+ .addReg(X86::R11, RegState::Kill);
+ } else {
+
+ // For non-large code model we can do direct call to __chkstk.
+
+ MIB = BuildMI(MBB, MBBI, DL, TII.get(X86::W64ALLOCA))
+ .addExternalSymbol(StackProbeSymbol);
+ }
} else {
// Allocate NumBytes-4 bytes on stack in case of isEAXAlive.
// We'll also use 4 already allocated bytes for EAX.
BuildMI(MBB, MBBI, DL, TII.get(X86::MOV32ri), X86::EAX)
.addImm(isEAXAlive ? NumBytes - 4 : NumBytes)
.setMIFlag(MachineInstr::FrameSetup);
+
+ MIB = BuildMI(MBB, MBBI, DL, TII.get(X86::CALLpcrel32))
+ .addExternalSymbol(StackProbeSymbol);
}
- BuildMI(MBB, MBBI, DL,
- TII.get(Is64Bit ? X86::W64ALLOCA : X86::CALLpcrel32))
- .addExternalSymbol(StackProbeSymbol)
- .addReg(StackPtr, RegState::Define | RegState::Implicit)
+
+ MIB.addReg(StackPtr, RegState::Define | RegState::Implicit)
.addReg(X86::EFLAGS, RegState::Define | RegState::Implicit)
.setMIFlag(MachineInstr::FrameSetup);
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