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FMA ZAligned name

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This commit is contained in:
David Harris 2022-07-02 19:35:13 +00:00
parent 9685a37a5f
commit 52dbc9f8be
1 changed files with 3 additions and 8 deletions
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11
pipelined/src/fpu/fma.sv
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@ -62,8 +62,7 @@ module fma(
// calculate the product's exponent
expadd expadd(.FmtE, .XExpE, .YExpE, .XZeroE, .YZeroE,
.ProdExpE);
expadd expadd(.FmtE, .XExpE, .YExpE, .XZeroE, .YZeroE, .ProdExpE);
// multiplication of the mantissa's
mult mult(.XManE, .YManE, .ProdManE);
@ -72,7 +71,7 @@ module fma(
// Alignment shifter
///////////////////////////////////////////////////////////////////////////////
align align(.ZExpE, .ZManE, .XZeroE, .YZeroE, .ZZeroE, .ProdExpE, .XExpE, .YExpE,
align align(.ZExpE, .ZManE, .XZeroE, .YZeroE, .ZZeroE, .XExpE, .YExpE,
.AlignedAddendE, .AddendStickyE, .KillProdE);
// calculate the signs and take the opperation into account
@ -88,8 +87,6 @@ module fma(
// Choose the positive sum and accompanying LZA result.
assign SumE = NegSumE ? NegPreSum[3*`NF+5:0] : PreSum[3*`NF+5:0];
endmodule
@ -151,7 +148,6 @@ module align(
input logic [`NE-1:0] XExpE, YExpE, ZExpE, // biased exponents in B(NE.0) format
input logic [`NF:0] ZManE, // fractions in U(0.NF) format]
input logic XZeroE, YZeroE, ZZeroE, // is the input zero
input logic [`NE+1:0] ProdExpE, // the product's exponent
output logic [3*`NF+5:0] AlignedAddendE, // Z aligned for addition in U(NF+5.2NF+1)
output logic AddendStickyE, // Sticky bit calculated from the aliged addend
output logic KillProdE // should the product be set to zero
@ -168,8 +164,7 @@ module align(
// determine the shift count for alignment
// - negitive means Z is larger, so shift Z left
// - positive means the product is larger, so shift Z right
// *** can we use ProdExpE instead of XExp/YExp to save an adder? DH 5/12/22
// KP- yes we used ProdExpE originally but we did this for timing
// This could have been done using ProdExpE, but AlignCnt is on the critical path so we replicate logic for speed
assign AlignCnt = XZeroE|YZeroE ? -(`NE+2)'($unsigned(1)) : {2'b0, XExpE} + {2'b0, YExpE} - {2'b0, (`NE)'(`BIAS)} + (`NE+2)'(`NF)+3 - {2'b0, ZExpE};
// Defualt Addition without shifting