1 files changed, 83 insertions, 0 deletions
diff --git a/contrib/llvm/patches/patch-06-llvm-r226664-aarch64-x18.diff b/contrib/llvm/patches/patch-06-llvm-r226664-aarch64-x18.diff
new file mode 100644
index 0000000..887d3aa
--- /dev/null
+++ b/contrib/llvm/patches/patch-06-llvm-r226664-aarch64-x18.diff
@@ -0,0 +1,83 @@
+Pull in r226664 from upstream llvm trunk (by Tim Northover):
+
+  AArch64: add backend option to reserve x18 (platform register)
+
+  AAPCS64 says that it's up to the platform to specify whether x18 is
+  reserved, and a first step on that way is to add a flag controlling
+  it.
+
+  From: Andrew Turner <andrew@fubar.geek.nz>
+
+Introduced here: http://svnweb.freebsd.org/changeset/base/277774
+
+Index: lib/Target/AArch64/AArch64RegisterInfo.cpp
+===================================================================
+--- lib/Target/AArch64/AArch64RegisterInfo.cpp
++++ lib/Target/AArch64/AArch64RegisterInfo.cpp
+@@ -33,6 +33,10 @@ using namespace llvm;
+ #define GET_REGINFO_TARGET_DESC
+ #include "AArch64GenRegisterInfo.inc"
+ 
++static cl::opt<bool>
++ReserveX18("aarch64-reserve-x18", cl::Hidden,
++          cl::desc("Reserve X18, making it unavailable as GPR"));
++
+ AArch64RegisterInfo::AArch64RegisterInfo(const AArch64InstrInfo *tii,
+                                          const AArch64Subtarget *sti)
+     : AArch64GenRegisterInfo(AArch64::LR), TII(tii), STI(sti) {}
+@@ -90,7 +94,7 @@ AArch64RegisterInfo::getReservedRegs(const Machine
+     Reserved.set(AArch64::W29);
+   }
+ 
+-  if (STI->isTargetDarwin()) {
++  if (STI->isTargetDarwin() || ReserveX18) {
+     Reserved.set(AArch64::X18); // Platform register
+     Reserved.set(AArch64::W18);
+   }
+@@ -117,7 +121,7 @@ bool AArch64RegisterInfo::isReservedReg(const Mach
+     return true;
+   case AArch64::X18:
+   case AArch64::W18:
+-    return STI->isTargetDarwin();
++    return STI->isTargetDarwin() || ReserveX18;
+   case AArch64::FP:
+   case AArch64::W29:
+     return TFI->hasFP(MF) || STI->isTargetDarwin();
+@@ -379,7 +383,7 @@ unsigned AArch64RegisterInfo::getRegPressureLimit(
+   case AArch64::GPR64commonRegClassID:
+     return 32 - 1                                      // XZR/SP
+            - (TFI->hasFP(MF) || STI->isTargetDarwin()) // FP
+-           - STI->isTargetDarwin() // X18 reserved as platform register
++           - (STI->isTargetDarwin() || ReserveX18) // X18 reserved as platform register
+            - hasBasePointer(MF);   // X19
+   case AArch64::FPR8RegClassID:
+   case AArch64::FPR16RegClassID:
+Index: test/CodeGen/AArch64/arm64-platform-reg.ll
+===================================================================
+--- test/CodeGen/AArch64/arm64-platform-reg.ll
++++ test/CodeGen/AArch64/arm64-platform-reg.ll
+@@ -1,4 +1,5 @@
+-; RUN: llc -mtriple=arm64-apple-ios -o - %s | FileCheck %s --check-prefix=CHECK-DARWIN
++; RUN: llc -mtriple=arm64-apple-ios -o - %s | FileCheck %s --check-prefix=CHECK-RESERVE-X18
++; RUN: llc -mtriple=arm64-freebsd-gnu -aarch64-reserve-x18 -o - %s | FileCheck %s --check-prefix=CHECK-RESERVE-X18
+ ; RUN: llc -mtriple=arm64-linux-gnu -o - %s | FileCheck %s
+ 
+ ; x18 is reserved as a platform register on Darwin but not on other
+@@ -16,11 +17,11 @@ define void @keep_live() {
+ ; CHECK: ldr x18
+ ; CHECK: str x18
+ 
+-; CHECK-DARWIN-NOT: ldr fp
+-; CHECK-DARWIN-NOT: ldr x18
+-; CHECK-DARWIN: Spill
+-; CHECK-DARWIN-NOT: ldr fp
+-; CHECK-DARWIN-NOT: ldr x18
+-; CHECK-DARWIN: ret
++; CHECK-RESERVE-X18-NOT: ldr fp
++; CHECK-RESERVE-X18-NOT: ldr x18
++; CHECK-RESERVE-X18: Spill
++; CHECK-RESERVE-X18-NOT: ldr fp
++; CHECK-RESERVE-X18-NOT: ldr x18
++; CHECK-RESERVE-X18: ret
+   ret void
+ }