diff options
| -rw-r--r-- | lib/Support/APInt.cpp | 43 | ||||
| -rw-r--r-- | test/Transforms/ConstProp/bswap.ll | 18 |
2 files changed, 43 insertions, 18 deletions
diff --git a/lib/Support/APInt.cpp b/lib/Support/APInt.cpp index 3774c52..55cb433 100644 --- a/lib/Support/APInt.cpp +++ b/lib/Support/APInt.cpp @@ -870,30 +870,43 @@ unsigned APInt::countPopulationSlowCase() const { return Count; } +/// Perform a logical right-shift from Src to Dst, which must be equal or +/// non-overlapping, of Words words, by Shift, which must be less than 64. +static void lshrNear(uint64_t *Dst, uint64_t *Src, unsigned Words, + unsigned Shift) { + uint64_t Carry = 0; + for (int I = Words - 1; I >= 0; --I) { + uint64_t Tmp = Src[I]; + Dst[I] = (Tmp >> Shift) | Carry; + Carry = Tmp << (64 - Shift); + } +} + APInt APInt::byteSwap() const { assert(BitWidth >= 16 && BitWidth % 16 == 0 && "Cannot byteswap!"); if (BitWidth == 16) return APInt(BitWidth, ByteSwap_16(uint16_t(VAL))); - else if (BitWidth == 32) + if (BitWidth == 32) return APInt(BitWidth, ByteSwap_32(unsigned(VAL))); - else if (BitWidth == 48) { + if (BitWidth == 48) { unsigned Tmp1 = unsigned(VAL >> 16); Tmp1 = ByteSwap_32(Tmp1); uint16_t Tmp2 = uint16_t(VAL); Tmp2 = ByteSwap_16(Tmp2); return APInt(BitWidth, (uint64_t(Tmp2) << 32) | Tmp1); - } else if (BitWidth == 64) + } + if (BitWidth == 64) return APInt(BitWidth, ByteSwap_64(VAL)); - else { - APInt Result(BitWidth, 0); - char *pByte = (char*)Result.pVal; - for (unsigned i = 0; i < BitWidth / APINT_WORD_SIZE / 2; ++i) { - char Tmp = pByte[i]; - pByte[i] = pByte[BitWidth / APINT_WORD_SIZE - 1 - i]; - pByte[BitWidth / APINT_WORD_SIZE - i - 1] = Tmp; - } - return Result; + + APInt Result(getNumWords() * APINT_BITS_PER_WORD, 0); + for (unsigned I = 0, N = getNumWords(); I != N; ++I) + Result.pVal[I] = ByteSwap_64(pVal[N - I - 1]); + if (Result.BitWidth != BitWidth) { + lshrNear(Result.pVal, Result.pVal, getNumWords(), + Result.BitWidth - BitWidth); + Result.BitWidth = BitWidth; } + return Result; } APInt llvm::APIntOps::GreatestCommonDivisor(const APInt& API1, @@ -1232,11 +1245,7 @@ APInt APInt::lshr(unsigned shiftAmt) const { // If we are shifting less than a word, compute the shift with a simple carry if (shiftAmt < APINT_BITS_PER_WORD) { - uint64_t carry = 0; - for (int i = getNumWords()-1; i >= 0; --i) { - val[i] = (pVal[i] >> shiftAmt) | carry; - carry = pVal[i] << (APINT_BITS_PER_WORD - shiftAmt); - } + lshrNear(val, pVal, getNumWords(), shiftAmt); return APInt(val, BitWidth).clearUnusedBits(); } diff --git a/test/Transforms/ConstProp/bswap.ll b/test/Transforms/ConstProp/bswap.ll index 9fce309..a68fdcd 100644 --- a/test/Transforms/ConstProp/bswap.ll +++ b/test/Transforms/ConstProp/bswap.ll @@ -1,6 +1,6 @@ ; bswap should be constant folded when it is passed a constant argument -; RUN: opt < %s -constprop -S | not grep call +; RUN: opt < %s -constprop -S | FileCheck %s declare i16 @llvm.bswap.i16(i16) @@ -8,18 +8,34 @@ declare i32 @llvm.bswap.i32(i32) declare i64 @llvm.bswap.i64(i64) +declare i80 @llvm.bswap.i80(i80) + +; CHECK: define i16 @W define i16 @W() { + ; CHECK: ret i16 256 %Z = call i16 @llvm.bswap.i16( i16 1 ) ; <i16> [#uses=1] ret i16 %Z } +; CHECK: define i32 @X define i32 @X() { + ; CHECK: ret i32 16777216 %Z = call i32 @llvm.bswap.i32( i32 1 ) ; <i32> [#uses=1] ret i32 %Z } +; CHECK: define i64 @Y define i64 @Y() { + ; CHECK: ret i64 72057594037927936 %Z = call i64 @llvm.bswap.i64( i64 1 ) ; <i64> [#uses=1] ret i64 %Z } +; CHECK: define i80 @Z +define i80 @Z() { + ; CHECK: ret i80 -450681596205739728166896 + ; 0xA0908070605040302010 + %Z = call i80 @llvm.bswap.i80( i80 76151636403560493650080 ) + ; 0x102030405060708090A0 + ret i80 %Z +} |