diff options
| author | ducky | 2016-05-05 11:50:39 -0700 |
|---|---|---|
| committer | ducky | 2016-05-05 11:50:39 -0700 |
| commit | 9036d96bb032c19de31131f2296120e708cbc3dc (patch) | |
| tree | cf17173fab309b09670ca7529680e09d61341451 /src/main/scala/Chisel/BitPat.scala | |
| parent | 623a301df1f5a1954f8e4a64ef97c99c3900da28 (diff) | |
Move Chisel API into separate chiselFrontend compilation unit in preparation for source locator macros
Diffstat (limited to 'src/main/scala/Chisel/BitPat.scala')
| -rw-r--r-- | src/main/scala/Chisel/BitPat.scala | 80 |
1 files changed, 0 insertions, 80 deletions
diff --git a/src/main/scala/Chisel/BitPat.scala b/src/main/scala/Chisel/BitPat.scala deleted file mode 100644 index a1bf1985..00000000 --- a/src/main/scala/Chisel/BitPat.scala +++ /dev/null @@ -1,80 +0,0 @@ -// See LICENSE for license details. - -package Chisel - -object BitPat { - /** Parses a bit pattern string into (bits, mask, width). - * - * @return bits the literal value, with don't cares being 0 - * @return mask the mask bits, with don't cares being 0 and cares being 1 - * @return width the number of bits in the literal, including values and - * don't cares. - */ - private def parse(x: String): (BigInt, BigInt, Int) = { - // Notes: - // While Verilog Xs also handle octal and hex cases, there isn't a - // compelling argument and no one has asked for it. - // If ? parsing is to be exposed, the return API needs further scrutiny - // (especially with things like mask polarity). - require(x.head == 'b', "BitPats must be in binary and be prefixed with 'b'") - var bits = BigInt(0) - var mask = BigInt(0) - for (d <- x.tail) { - if (d != '_') { - require("01?".contains(d), "Literal: " + x + " contains illegal character: " + d) - mask = (mask << 1) + (if (d == '?') 0 else 1) - bits = (bits << 1) + (if (d == '1') 1 else 0) - } - } - (bits, mask, x.length - 1) - } - - /** Creates a [[BitPat]] literal from a string. - * - * @param n the literal value as a string, in binary, prefixed with 'b' - * @note legal characters are '0', '1', and '?', as well as '_' as white - * space (which are ignored) - */ - def apply(n: String): BitPat = { - val (bits, mask, width) = parse(n) - new BitPat(bits, mask, width) - } - - /** Creates a [[BitPat]] of all don't cares of the specified bitwidth. */ - def dontCare(width: Int): BitPat = BitPat("b" + ("?" * width)) - - @deprecated("Use BitPat.dontCare", "chisel3") - def DC(width: Int): BitPat = dontCare(width) // scalastyle:ignore method.name - - /** Allows BitPats to be used where a UInt is expected. - * - * @note the BitPat must not have don't care bits (will error out otherwise) - */ - implicit def bitPatToUInt(x: BitPat): UInt = { - require(x.mask == (BigInt(1) << x.getWidth) - 1) - UInt(x.value, x.getWidth) - } - - /** Allows UInts to be used where a BitPat is expected, useful for when an - * interface is defined with BitPats but not all cases need the partial - * matching capability. - * - * @note the UInt must be a literal - */ - implicit def apply(x: UInt): BitPat = { - require(x.isLit) - BitPat("b" + x.litValue.toString(2)) - } -} - -// TODO: Break out of Core? (this doesn't involve FIRRTL generation) -/** Bit patterns are literals with masks, used to represent values with don't - * cares. Equality comparisons will ignore don't care bits (for example, - * BitPat(0b10?1) === UInt(0b1001) and UInt(0b1011)). - */ -sealed class BitPat(val value: BigInt, val mask: BigInt, width: Int) { - def getWidth: Int = width - def === (other: UInt): Bool = UInt(value) === (other & UInt(mask)) - def =/= (other: UInt): Bool = !(this === other) - def != (other: UInt): Bool = this =/= other -} |
