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| author | Reid Spencer <rspencer@reidspencer.com> | 2007-03-02 01:19:42 +0000 |
|---|---|---|
| committer | Reid Spencer <rspencer@reidspencer.com> | 2007-03-02 01:19:42 +0000 |
| commit | 36184ed4cd8dc0dc302b8f51f169c334b7460168 (patch) | |
| tree | a16381bcee74ba73de6d9855d6ef130ca54025ca /lib/Support/APInt.cpp | |
| parent | 9f8e50d4ed7dcc5ca0f137830ff1185b2afa38bf (diff) | |
Fix a problem where shifting by 64-bits leads to incorrect results on PPC
but not on X86 becuase shift by word size is "undefined".
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34825 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Support/APInt.cpp')
| -rw-r--r-- | lib/Support/APInt.cpp | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/lib/Support/APInt.cpp b/lib/Support/APInt.cpp index 9b000da0ee..36f88a2479 100644 --- a/lib/Support/APInt.cpp +++ b/lib/Support/APInt.cpp @@ -938,7 +938,10 @@ APInt &APInt::sext(uint32_t width) { if (wordsBefore == wordsAfter) { uint32_t newWordBits = width % APINT_BITS_PER_WORD; // The extension is contained to the wordsBefore-1th word. - uint64_t mask = (~0ULL >> (APINT_BITS_PER_WORD - newWordBits)) << wordBits; + uint64_t mask = ~0ULL; + if (newWordBits) + mask >>= APINT_BITS_PER_WORD - newWordBits; + mask <<= wordBits; if (wordsBefore == 1) VAL |= mask; else |