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llvm-svn: 145896
2011-12-06 01:57:48 +00:00 · 2011-12-06 01:57:48 +00:00 · 4e87e850a2
parent 425e180ce8
commit 4e87e850a2
1 changed files with 3 additions and 0 deletions
--- a/llvm/lib/Target/X86/X86FrameLowering.cpp
+++ b/llvm/lib/Target/X86/X86FrameLowering.cpp
@ -456,6 +456,9 @@ static uint32_t encodeCompactUnwindRegistersWithFrame(unsigned SavedRegs[6],
    int CURegNum = getCompactUnwindRegNum(CURegs, Reg);
    if (CURegNum == -1)
      return ~0U;
+
+    // Encode the 3-bit register number in order, skipping over 3-bits for each
+    // register.
    RegEnc |= (CURegNum & 0x7) << ((5 - I) * 3);
  }