[PATCH] D46552: [AArch64] Support reserving x19 and x20 register

[Eli Friedman via Phabricator via llvm-commits]

efriedma added inline comments.


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Comment at: llvm/lib/Target/AArch64/AArch64RegisterInfo.cpp:170
+  case AArch64::W19:
+    return MF.getSubtarget<AArch64Subtarget>().isX19Reserved() || hasBasePointer(MF);
+  case AArch64::X20:
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As you sort of note here, -ffixed-x19 conflicts with LLVM's usage of x19 as the base pointer (in functions which have dynamic allocas).  Granted, LLVM could be changed to use a different register for this, but currently you'll just miscompile.


Repository:
  rL LLVM

https://reviews.llvm.org/D46552