From: Tom Stellard <thomas.stellard@amd.com>
Date: Wed, 24 Sep 2014 01:33:23 +0000 (+0000)
Subject: R600/SI: Mark EXEC_LO and EXEC_HI as reserved
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=90d1726693a8d8b48cd4ba8308d2ef22772d394e;p=oota-llvm.git

R600/SI: Mark EXEC_LO and EXEC_HI as reserved

These registers can be allocated and used like other 32-bit registers,
but it seems like a likely source for bugs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218350 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/R600/SIRegisterInfo.cpp b/lib/Target/R600/SIRegisterInfo.cpp
index e443deb7ea9..f5307f88038 100644
--- a/lib/Target/R600/SIRegisterInfo.cpp
+++ b/lib/Target/R600/SIRegisterInfo.cpp
@@ -32,6 +32,12 @@ SIRegisterInfo::SIRegisterInfo(const AMDGPUSubtarget &st)
 BitVector SIRegisterInfo::getReservedRegs(const MachineFunction &MF) const {
   BitVector Reserved(getNumRegs());
   Reserved.set(AMDGPU::EXEC);
+
+  // EXEC_LO and EXEC_HI could be allocated and used as regular register,
+  // but this seems likely to result in bugs, so I'm marking them as reserved.
+  Reserved.set(AMDGPU::EXEC_LO);
+  Reserved.set(AMDGPU::EXEC_HI);
+
   Reserved.set(AMDGPU::INDIRECT_BASE_ADDR);
   Reserved.set(AMDGPU::FLAT_SCR);