[Fuchsia] Magenta -> Zircon

[mcgrathr]

Summary

Fuchsia's lowest API layer has been renamed from Magenta to Zircon.
In LLVM proper, this is only mentioned in comments.

[phosek]

LGTM

llvm/trunk/lib/Target/AArch64/AArch64ISelLowering.cpp

 Value *AArch64TargetLowering::getIRStackGuard(IRBuilder<> &IRB) const {
   // Android provides a fixed TLS slot for the stack cookie. See the definition
   // of TLS_SLOT_STACK_GUARD in
   // https://android.googlesource.com/platform/bionic/+/master/libc/private/bionic_tls.h
   if (Subtarget->isTargetAndroid())
     return UseTlsOffset(IRB, 0x28);
 
   // Fuchsia is similar.
-  // <magenta/tls.h> defines MX_TLS_STACK_GUARD_OFFSET with this value.
+  // <zircon/tls.h> defines ZX_TLS_STACK_GUARD_OFFSET with this value.
   if (Subtarget->isTargetFuchsia())
     return UseTlsOffset(IRB, -0x10);
 
   return TargetLowering::getIRStackGuard(IRB);
 }
 
 Value *AArch64TargetLowering::getSafeStackPointerLocation(IRBuilder<> &IRB) const {
   // Android provides a fixed TLS slot for the SafeStack pointer. See the
   // definition of TLS_SLOT_SAFESTACK in
   // https://android.googlesource.com/platform/bionic/+/master/libc/private/bionic_tls.h
   if (Subtarget->isTargetAndroid())
     return UseTlsOffset(IRB, 0x48);
 
   // Fuchsia is similar.
-  // <magenta/tls.h> defines MX_TLS_UNSAFE_SP_OFFSET with this value.
+  // <zircon/tls.h> defines ZX_TLS_UNSAFE_SP_OFFSET with this value.
   if (Subtarget->isTargetFuchsia())
     return UseTlsOffset(IRB, -0x8);
 
   return TargetLowering::getSafeStackPointerLocation(IRB);
 }
 
 bool AArch64TargetLowering::isMaskAndCmp0FoldingBeneficial(
     const Instruction &AndI) const {

llvm/trunk/lib/Target/X86/X86ISelLowering.cpp

 }
 
 Value *X86TargetLowering::getIRStackGuard(IRBuilder<> &IRB) const {
   // glibc, bionic, and Fuchsia have a special slot for the stack guard in
   // tcbhead_t; use it instead of the usual global variable (see
   // sysdeps/{i386,x86_64}/nptl/tls.h)
   if (hasStackGuardSlotTLS(Subtarget.getTargetTriple())) {
     if (Subtarget.isTargetFuchsia()) {
-      // <magenta/tls.h> defines MX_TLS_STACK_GUARD_OFFSET with this value.
+      // <zircon/tls.h> defines ZX_TLS_STACK_GUARD_OFFSET with this value.
       return SegmentOffset(IRB, 0x10, getAddressSpace());
     } else {
       // %fs:0x28, unless we're using a Kernel code model, in which case
       // it's %gs:0x28.  gs:0x14 on i386.
       unsigned Offset = (Subtarget.is64Bit()) ? 0x28 : 0x14;
       return SegmentOffset(IRB, Offset, getAddressSpace());
     }
   }
if (Subtarget.isTargetAndroid()) {
     // %fs:0x48, unless we're using a Kernel code model, in which case it's %gs:
     // %gs:0x24 on i386
     unsigned Offset = (Subtarget.is64Bit()) ? 0x48 : 0x24;
     return SegmentOffset(IRB, Offset, getAddressSpace());
   }
 
   // Fuchsia is similar.
   if (Subtarget.isTargetFuchsia()) {
-    // <magenta/tls.h> defines MX_TLS_UNSAFE_SP_OFFSET with this value.
+    // <zircon/tls.h> defines ZX_TLS_UNSAFE_SP_OFFSET with this value.
     return SegmentOffset(IRB, 0x18, getAddressSpace());
   }
 
   return TargetLowering::getSafeStackPointerLocation(IRB);
 }
 
 bool X86TargetLowering::isNoopAddrSpaceCast(unsigned SrcAS,
                                             unsigned DestAS) const {