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Fold in changes from SVN into CHERICC_Fat up to r34349

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This commit is contained in:
Peter Rugg
2019-03-20 12:39:59 +00:00
parent 671804575f
commit 3d9c6cc2ce
1 changed files with 17 additions and 4 deletions
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21
CHERICC_Fat.bsv
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@@ -250,13 +250,15 @@ Bool imprecise = True;
function LCapAddress getBotFat(CapFat cap, TempFields tf);
// First, construct a full length value with the base bits and the
// correction bits above, and shift that value to the appropriate spot.
LCapAddress addBase = signExtend({pack(tf.baseCorrection), cap.bounds.baseBits}) << cap.bounds.exp;
CapAddress addBase = signExtend({pack(tf.baseCorrection), cap.bounds.baseBits}) << cap.bounds.exp;
// Build a mask on the high bits of a full length value to extract the high
// bits of the address.
Bit#(TSub#(SizeOf#(LCapAddress),MW)) mask = ~0 << cap.bounds.exp;
Bit#(TSub#(SizeOf#(CapAddress),MW)) mask = ~0 << cap.bounds.exp;
// Extract the high bits of the address (and append the implied zeros at the
// bottom), and add with the previously prepared value.
return {truncateLSB(cap.address)&mask,0} + addBase;
CapAddress adr = truncate(cap.address); // Trim top bits of address.
CapAddress bot = {truncateLSB(adr)&mask,0} + addBase;
return zeroExtend(bot);
endfunction
function LCapAddress getTopFat(CapFat cap, TempFields tf);
// First, construct a full length value with the top bits and the
@@ -265,9 +267,18 @@ function LCapAddress getTopFat(CapFat cap, TempFields tf);
// Build a mask on the high bits of a full length value to extract the high
// bits of the address.
Bit#(TSub#(SizeOf#(LCapAddress),MW)) mask = ~0 << cap.bounds.exp;
Bool baseBelow = (tf.addrHi && !tf.baseHi);
Bool upperBitsZero = (truncateLSB(cap.address) & mask)==0;
Bit#(2) topBitsOfAddress = (baseBelow && upperBitsZero) ? 1:0;
cap.address = {topBitsOfAddress,truncate(cap.address)};
// Extract the high bits of the address (and append the implied zeros at the
// bottom), and add with the previously prepared value.
return {truncateLSB(cap.address)&mask,0} + addTop;
LCapAddress ret = {truncateLSB(cap.address)&mask,0} + addTop;
// Zero the top two bits of top is top and base are in the same region as the base
// can never have the top bit set. This solves the wrap-around at the bottom of
// the address space.
if ((tf.baseHi == tf.topHi) && (cap.bounds.exp < (resetExp - 1))) ret = ret & {2'b0,-1};
return ret;
endfunction
function LCapAddress getLengthFat(CapFat cap, TempFields tf);
// Get the top and base bits with the 2 correction bits prepended
@@ -329,6 +340,8 @@ function CapFat nullifyCap(CapFat cap);
CapAddress tmpAddr = truncate(cap.address);
ret.addrBits = {2'b0,truncateLSB(tmpAddr)};
ret.address = cap.address;
//CapFat ret = cap;
//ret.isCapability = False;
return ret;
endfunction
function CapFat pccJumpUpdate(CapFat pcc, LCapAddress fullBot);