this to a NOTE: because pari/gp results start to get rounded incorrectly
after 192 bits of precision. APInt and pari/gp never differ by more than
1, but APInt is more accurate because it does not lose precision after 192
bits as does pari/gp.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34834 91177308-0d34-0410-b5e6-96231b3b80d8
the bit width of negative numbers by computing the minimum bit width for a
negative value. E.g. 0x1800000000000000 could be just 0x8000000000000000
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34695 91177308-0d34-0410-b5e6-96231b3b80d8
1. Add unsigned and signed versions of methods so a "bool" argument doesn't
need to be passed in.
2. Make the various getMin/getMax functions all be inline since they are
so simple.
3. Simplify sdiv and srem code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34680 91177308-0d34-0410-b5e6-96231b3b80d8
2. Change RoundDoubleToAPInt to take a bit width parameter. Use that
parameter to limit the bit width of the result.
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2. Rewrite operator=(const APInt& RHS) to allow the RHS to be a different
bit width than the LHS. This makes it possible to use APInt as the key
of a DenseMap, as needed for the IntConstants map in Constants.cpp
3. Fix operator=(uint64_t) to clear unused bits in case the client assigns
a value that has more bits than the APInt allows.
4. Assert that bit widths are equal in operator==
5. Revise getHashValue() to put the bit width in the low order six bits.
This should help to make i1 0, i2 0, ... i64 0 all distinct in the
IntConstants DenseMap.
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2. Fix countTrailingZeros to use a faster algorithm.
3. Simplify sext() slightly by using isNegative().
4. Implement ashr using word-at-a-time logic instead of bit-at-a-time
5. Rename locals named isNegative so they don't clash with method name.
6. Fix fromString to compute negated value correctly.
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2. Implement the trunc, sext, and zext operations.
3. Improve fromString to accept negative values as input.
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2. Move comments for methods to .h file, delete them in .cpp file.
3. All places that were doing manual clear of high order bits now call the
clearUnusedBits() method in order to not depend on undefined behavior
of the >> operator when the number of bits shifted equals the word size.
4. Reduced # of loc by using the new result of clearUnusedBits() method.
5. Simplified logic (decreased indentation) in a few places.
6. Added code comments to larger functions that needed them.
7. Added FIXME notes about weak implementations of things (e.g. bit-by-bit
shift right is sub-optimal).
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2. Clean up comments, style, coding standards, etc.
3. Simplify a constructor.
Extended testing revealed some additional bugs in shifting. I'll fix these
tomorrow.
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to be safe.
2. Make internal functions that return a carry/borrow return bool instead
of uint64_t because the carry/borrow can only be in range [0,1].
3. Assert that the pointers to KnuthDiv are all different so that the
result and operands can't overlap.
4. Add debug output to KnuthDiv function.
5. Fix a problem with KnuthDiv by separating the b's complement operation
from the subtraction borrow operation. This fixes a wide range of
division problems, but alas, not all of them.
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memory (as done in fromString).
2. Implement Knuth divide more closely to what is recommended in his book.
3. Fix computation of the remainder for Knuth Divide (bad shifting).
4. Remove some cruft from the file
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extract the value, not the number of words implied by the active bits.
This fixes numerous, but not all divide bugs.
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word size. This fixes all reads of uninitialized data (buffer over read)
and makes APInt.cpp memory clean, per valgrind. The only remaining
problem is division in a few cases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34483 91177308-0d34-0410-b5e6-96231b3b80d8
