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author | Ian Lance Taylor <ian@airs.com> | 2012-01-28 01:47:01 +0000 |
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committer | Ian Lance Taylor <ian@airs.com> | 2012-01-28 01:47:01 +0000 |
commit | bef2b4345273a0279d89f5b79037eab6279d2883 (patch) | |
tree | 4f951e5c81cd397d9ad0fe4550474b2b3595b7e7 /gold/reloc.h | |
parent | 687a9c3959a60a93a1846e749ad5f3835e0183ea (diff) | |
download | gdb-bef2b4345273a0279d89f5b79037eab6279d2883.zip gdb-bef2b4345273a0279d89f5b79037eab6279d2883.tar.gz gdb-bef2b4345273a0279d89f5b79037eab6279d2883.tar.bz2 |
* reloc.h (Bits): New class with static functions, copied from
namespace utils in arm.cc.
* arm.cc (namespace utils): Remove. Rewrite all uses to use Bits
instead.
Diffstat (limited to 'gold/reloc.h')
-rw-r--r-- | gold/reloc.h | 119 |
1 files changed, 118 insertions, 1 deletions
diff --git a/gold/reloc.h b/gold/reloc.h index 02f91a4..973adb0 100644 --- a/gold/reloc.h +++ b/gold/reloc.h @@ -1,6 +1,7 @@ // reloc.h -- relocate input files for gold -*- C++ -*- -// Copyright 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc. +// Copyright 2006, 2007, 2008, 2009, 2010, 2011, 2012 +// Free Software Foundation, Inc. // Written by Ian Lance Taylor <iant@google.com>. // This file is part of gold. @@ -715,6 +716,122 @@ public: { This::template pcrela<64>(view, object, psymval, addend, address); } }; +// Integer manipulation functions used by various targets when +// performing relocations. + +template<int bits> +class Bits +{ + public: + // Sign extend an n-bit unsigned integer stored in a uint32_t into + // an int32_t. BITS must be between 0 and 32. + static inline int32_t + sign_extend32(uint32_t val) + { + gold_assert(bits >= 0 && bits <= 32); + if (bits == 32) + return static_cast<int32_t>(val); + uint32_t mask = (~static_cast<uint32_t>(0)) >> (32 - bits); + val &= mask; + uint32_t top_bit = 1U << (bits - 1); + int32_t as_signed = static_cast<int32_t>(val); + if ((val & top_bit) != 0) + as_signed -= static_cast<int32_t>(top_bit * 2); + return as_signed; + } + + // Return true if VAL (stored in a uint32_t) has overflowed a signed + // value with BITS bits. + static inline bool + has_overflow32(uint32_t val) + { + gold_assert(bits >= 0 && bits <= 32); + if (bits == 32) + return false; + int32_t max = (1 << (bits - 1)) - 1; + int32_t min = -(1 << (bits - 1)); + int32_t as_signed = static_cast<int32_t>(val); + return as_signed > max || as_signed < min; + } + + // Return true if VAL (stored in a uint32_t) has overflowed both a + // signed and an unsigned value. E.g., + // Bits<8>::has_signed_unsigned_overflow32 would check -128 <= VAL < + // 255. + static inline bool + has_signed_unsigned_overflow32(uint32_t val) + { + gold_assert(bits >= 0 && bits <= 32); + if (bits == 32) + return false; + int32_t max = static_cast<int32_t>((1U << bits) - 1); + int32_t min = -(1 << (bits - 1)); + int32_t as_signed = static_cast<int32_t>(val); + return as_signed > max || as_signed < min; + } + + // Select bits from A and B using bits in MASK. For each n in + // [0..31], the n-th bit in the result is chosen from the n-th bits + // of A and B. A zero selects A and a one selects B. + static inline uint32_t + bit_select32(uint32_t a, uint32_t b, uint32_t mask) + { return (a & ~mask) | (b & mask); } + + // Sign extend an n-bit unsigned integer stored in a uint64_t into + // an int64_t. BITS must be between 0 and 64. + static inline int64_t + sign_extend(uint64_t val) + { + gold_assert(bits >= 0 && bits <= 64); + if (bits == 64) + return static_cast<int64_t>(val); + uint64_t mask = (~static_cast<uint64_t>(0)) >> (64 - bits); + val &= mask; + uint64_t top_bit = static_cast<uint64_t>(1) << (bits - 1); + int64_t as_signed = static_cast<int64_t>(val); + if ((val & top_bit) != 0) + as_signed -= static_cast<int64_t>(top_bit * 2); + return as_signed; + } + + // Return true if VAL (stored in a uint64_t) has overflowed a signed + // value with BITS bits. + static inline bool + has_overflow(uint64_t val) + { + gold_assert(bits >= 0 && bits <= 64); + if (bits == 64) + return false; + int64_t max = (static_cast<int64_t>(1) << (bits - 1)) - 1; + int64_t min = -(static_cast<int64_t>(1) << (bits - 1)); + int64_t as_signed = static_cast<int64_t>(val); + return as_signed > max || as_signed < min; + } + + // Return true if VAL (stored in a uint64_t) has overflowed both a + // signed and an unsigned value. E.g., + // Bits<8>::has_signed_unsigned_overflow would check -128 <= VAL < + // 255. + static inline bool + has_signed_unsigned_overflow64(uint64_t val) + { + gold_assert(bits >= 0 && bits <= 64); + if (bits == 64) + return false; + int64_t max = static_cast<int64_t>((static_cast<uint64_t>(1) << bits) - 1); + int64_t min = -(static_cast<int64_t>(1) << (bits - 1)); + int64_t as_signed = static_cast<int64_t>(val); + return as_signed > max || as_signed < min; + } + + // Select bits from A and B using bits in MASK. For each n in + // [0..31], the n-th bit in the result is chosen from the n-th bits + // of A and B. A zero selects A and a one selects B. + static inline uint64_t + bit_select64(uint64_t a, uint64_t b, uint64_t mask) + { return (a & ~mask) | (b & mask); } +}; + // Track relocations while reading a section. This lets you ask for // the relocation at a certain offset, and see how relocs occur // between points of interest. |