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Ivan00's avatar
Ivan00
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4 years ago

Bug report: synthesis optimizes out the signal if data type is declared in generic package

When the data type is declared in the generic package, the synthesis tool removes the signal completely when array slice is used on the right side of the assignment. I have condensed it to the follow...
Ivan00's avatar
Ivan00
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4 years ago

Hi Ean,

i have chosen different output bus size in order to demonstrate the bug. The bug manifests itself when subscript is used on the right side.

When I resize the bus, the o_bug[16 downto 0] must be connected to i[16 downto 0], only bit 17 should be removed. Instead the whole connection is removed.

This happens only if the type test_type_t is defined in a generic package.

Best regards,

Ivan

YEan's avatar
YEan
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4 years ago

Hi Ivan,

If the bus length of input and output were different the Quartus will show error messages. You may consider to change the architecture in your design to fulfill your requirement.

Thanks,

Ean