[SystemZ] Save/restore r6 and r7 if function contains landing pad.

Marcin Koscielnicki · Marcin Koscielnicki · commit 234e5a809b49 · 2016-06-28T14:13:11.000Z
This fixes PR27102. Differential Revision: http://reviews.llvm.org/D18541 llvm-svn: 274017
diff --git a/llvm/lib/Target/SystemZ/SystemZFrameLowering.cpp b/llvm/lib/Target/SystemZ/SystemZFrameLowering.cpp
@@ -81,6 +81,12 @@ void SystemZFrameLowering::determineCalleeSaves(MachineFunction &MF,
     for (unsigned I = MFI->getVarArgsFirstGPR(); I < SystemZ::NumArgGPRs; ++I)
       SavedRegs.set(SystemZ::ArgGPRs[I]);
 
+  // If there are any landing pads, entering them will modify r6/r7.
+  if (!MF.getMMI().getLandingPads().empty()) {
+    SavedRegs.set(SystemZ::R6D);
+    SavedRegs.set(SystemZ::R7D);
+  }
+
   // If the function requires a frame pointer, record that the hard
   // frame pointer will be clobbered.
   if (HasFP)
diff --git a/llvm/test/DebugInfo/SystemZ/eh_frame_personality.ll b/llvm/test/DebugInfo/SystemZ/eh_frame_personality.ll
@@ -20,7 +20,9 @@ clean:
 ; CHECK-FUNC: .cfi_startproc
 ; CHECK-FUNC: .cfi_personality 0, __gxx_personality_v0
 ; CHECK-FUNC: .cfi_lsda 0, .Lexception0
-; CHECK-FUNC: stmg	%r14, %r15, 112(%r15)
+; CHECK-FUNC: stmg	%r6, %r15, 48(%r15)
+; CHECK-FUNC: .cfi_offset %r6, -112
+; CHECK-FUNC: .cfi_offset %r7, -104
 ; CHECK-FUNC: .cfi_offset %r14, -48
 ; CHECK-FUNC: .cfi_offset %r15, -40
 ; CHECK-FUNC: aghi	%r15, -160
