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Respect \A_SIGNED for $shift

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This reflects the behaviour of $shr/$shl, which sign-extend their A
operands to the size of their output, then do a logical shift (shift in
0-bits).
This commit is contained in:
Xiretza 2020-07-03 13:13:21 +02:00 • committed by Marcelina Kościelnicka
parent 22765ef0a5
commit 928fd40c2e
7 changed files with 61 additions and 65 deletions
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16
techlibs/common/simlib.v
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@ -480,10 +480,18 @@ input [B_WIDTH-1:0] B;
output [Y_WIDTH-1:0] Y;
generate
if (B_SIGNED) begin:BLOCK1
assign Y = $signed(B) < 0 ? A << -B : A >> B;
end else begin:BLOCK2
assign Y = A >> B;
if (A_SIGNED) begin:BLOCK1
if (B_SIGNED) begin:BLOCK2
assign Y = $signed(B) < 0 ? $signed(A) << -B : $signed(A) >> B;
end else begin:BLOCK3
assign Y = $signed(A) >> B;
end
end else begin:BLOCK4
if (B_SIGNED) begin:BLOCK5
assign Y = $signed(B) < 0 ? A << -B : A >> B;
end else begin:BLOCK6
assign Y = A >> B;
end
end
endgenerate