def CSR_Darwin_AArch64_AAVPCS : CalleeSavedRegs<(add LR, FP, X19, X20, X21,
X22, X23, X24, X25, X26, X27,
X28, (sequence "Q%u", 8, 23))>;
+
+// For Windows calling convention on a non-windows OS, where X18 is treated
+// as reserved, back up X18 when entering non-windows code (marked with the
+// Windows calling convention) and restore when returning regardless of
+// whether the individual function uses it - it might call other functions
+// that clobber it.
+def CSR_Darwin_AArch64_AAPCS_Win64
+ : CalleeSavedRegs<(add CSR_Darwin_AArch64_AAPCS, X18)>;
+
def CSR_Darwin_AArch64_AAPCS_ThisReturn
: CalleeSavedRegs<(add CSR_Darwin_AArch64_AAPCS, X0)>;
(void)CC;
// MachO's compact unwind format relies on all registers being stored in
// pairs.
- assert((!produceCompactUnwindFrame(MF) ||
- CC == CallingConv::PreserveMost || CC == CallingConv::CXX_FAST_TLS ||
+ assert((!produceCompactUnwindFrame(MF) || CC == CallingConv::PreserveMost ||
+ CC == CallingConv::CXX_FAST_TLS || CC == CallingConv::Win64 ||
(Count & 1) == 0) &&
"Odd number of callee-saved regs to spill!");
int ByteOffset = AFI->getCalleeSavedStackSize();
// MachO's compact unwind format relies on all registers being stored in
// adjacent register pairs.
- assert((!produceCompactUnwindFrame(MF) ||
- CC == CallingConv::PreserveMost || CC == CallingConv::CXX_FAST_TLS ||
+ assert((!produceCompactUnwindFrame(MF) || CC == CallingConv::PreserveMost ||
+ CC == CallingConv::CXX_FAST_TLS || CC == CallingConv::Win64 ||
(RPI.isPaired() &&
((RPI.Reg1 == AArch64::LR && RPI.Reg2 == AArch64::FP) ||
RPI.Reg1 + 1 == RPI.Reg2))) &&
return CSR_Darwin_AArch64_AAPCS_SwiftTail_SaveList;
if (MF->getFunction().getCallingConv() == CallingConv::PreserveMost)
return CSR_Darwin_AArch64_RT_MostRegs_SaveList;
+ if (MF->getFunction().getCallingConv() == CallingConv::Win64)
+ return CSR_Darwin_AArch64_AAPCS_Win64_SaveList;
return CSR_Darwin_AArch64_AAPCS_SaveList;
}
--- /dev/null
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+
+;; Testing that x18 is backed up and restored, and that x29 (if used) still
+;; points to the x29,x30 pair on the stack.
+
+; RUN: llc < %s -mtriple=arm64-apple-darwin | FileCheck %s
+; RUN: llc < %s -mtriple=arm64-apple-darwin -mattr=+reserve-x18 | FileCheck %s
+
+declare dso_local void @other()
+
+define win64cc void @func(i32 noundef %0) #0 {
+; CHECK-LABEL: func:
+; CHECK: ; %bb.0: ; %entry
+; CHECK-NEXT: str x18, [sp, #-32]! ; 8-byte Folded Spill
+; CHECK-NEXT: stp x29, x30, [sp, #16] ; 16-byte Folded Spill
+; CHECK: ldp x29, x30, [sp, #16] ; 16-byte Folded Reload
+; CHECK-NEXT: ldr x18, [sp], #32 ; 8-byte Folded Reload
+; CHECK-NEXT: ret
+entry:
+ %al = alloca i32, align 4
+ store i32 %0, ptr %al, align 4
+ tail call void @other()
+ ret void
+}
+
+define i32 @main() {
+ call win64cc void @func(i32 noundef 17)
+ ret i32 0
+}
+
+attributes #0 = { nounwind }