JPH05250439A - Cell placement system - Google Patents

Abstract

(57) [Abstract] [Purpose] A data path compiler, which is an automatic layout tool for the data path section, efficiently arranges the function macro of the register transfer level circuit and the cells of the leaf cell level circuit of the lower hierarchy. [Structure] A circuit diagram as shown in (A) is arranged between placement instruction symbols as shown in (B), leaf cell circuits corresponding to the respective function macros are loaded from a library circuit diagram file, and further placed between placement instruction symbols. , The relative position to each function macro is detected, the hierarchy is expanded and the position is calculated, and the cell placement result is obtained as in (C). [Effect] By applying the placement instruction symbol to the cell placement, it is possible to visually perform the placement operation, save the labor of inputting attributes, and easily adjust the placement information on the layout. You can perform placement operations that are not limited by size.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cell placement system, and more particularly to a cell placement system in a data path circuit section of an automatic layout system.

[0002]

2. Description of the Related Art In a conventional cell placement system in a data path circuit, when a circuit diagram file as shown in FIG. 2 is present, two-dimensional coordinates are directly extracted in each of the function macros 201 to 204 on the circuit diagram. However, there is a system that determines the cell layout on the layout by using it as layout information, and a system that assigns an attribute to each function macro and uses it as layout information. The flow chart is shown in FIG. The register-transfer circuit file 101 is a circuit diagram file as shown in FIG. 2. Using this file, a library circuit diagram file 107 and a leaf cell layout file 110 which are information files necessary for cell placement, The placement result file 702 is output. In order to output the cell placement result, all the edits 701 were performed manually to perform placement information processing.

[0003]

In this conventional cell placement system, there are means for directly extracting coordinates from the register transfer circuit diagram to function macros and leaf cells, and means for giving attributes. The former is the coordinates. Therefore, it is difficult to make adjustments to the layout information on the layout because of the drawback that it is necessary to pay attention even to the numerically detailed parts and it is extremely difficult to draw the circuit diagram. Further, the latter has a problem that it takes time to input the attribute.

[0004]

According to the cell placement system of the present invention, in a data path compiler which is an automatic layout tool for a data path section, a function macro on a register transfer level circuit diagram is placed between placement instruction symbols. A feature is that the cell placement on the layout is determined using the placement information obtained by placement and the placement information of the arrangement of the leaf cells in the lower hierarchy on the circuit diagram.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings. FIG. 1 is a flow chart of an embodiment of the present invention. The register transfer circuit diagram file 101 is a circuit diagram file as shown in FIG.
1 to 204 are arranged by the layout editing 102 in FIG. 1 and each function macro is arranged between the layout designating symbols 301 as shown in FIG. 3 to create the register transfer layout file 103 in FIG. The leaf cell group as shown in FIG. 4 corresponding to each function macro is shown in FIG.
1 from the library circuit diagram file 107 of FIG.
The information is arranged by the layout editing 106 of FIG. 5, and the leaf cell group 40 is arranged between the layout designating symbols 301 as shown in FIG.
1 to 404 are arranged and relative position detection 104 with 103 of FIG. 1 is performed. Further, each function macro is expanded to the leaf cell level by the hierarchical expansion 108 of FIG. 1, the arrangement information is obtained from the leaf cell layout file 110 of FIG. 1, and the file in which the cell arrangement as shown in FIG. Create and create this cell placement result file 111 in FIG.
Is output as.

FIG. 2 shows an example of a circuit contained in the register transfer circuit diagram file shown in FIG.

FIG. 3 shows the register transfer layout diagram 103 of FIG. 1, and each functional macro 201 of FIG.
To 204 are arranged between the arrangement instruction symbols 301. Reference numeral 205 denotes the origin of each symbol, and the origin is arranged between the placement instruction symbols with reference to this. Also,
The placement instruction symbol is an axis that has graduations at equal intervals in the x-axis direction, and if the origin of the symbol enters that section, the same x-axis will be used no matter where the origin is placed within that section. Considered to be a row of.

FIG. 4 shows an example of a leaf cell level circuit included in the library circuit diagram file 107 of FIG. The circuits corresponding to the respective function macros 201 to 204 of FIG. 2 are contained in the 107 file. 40
1 to 404 are leaf cells, which are lower layers of each function macro.

FIG. 5 shows an example of one layout diagram in the library circuit layout file 105 shown in FIG.
6 is arranged. The placement instruction symbol here has a different scale from that of FIG. 3 and therefore has a different scale.

FIG. 6 shows a result file output as a result of the embodiment. Reference numerals 601 to 616 represent leaf cells. 601 to 604 are leaf cell groups of the lower layer 201 of FIG. 2, 605 to 608 are leaf cell groups of the lower layer of 202, and 609 to 612 are leaf cells of the lower layer of 203. The groups 613 to 616 represent leaf cell groups of the lower hierarchy of 204. The arrangement depends on the function macro arranged between the arrangement designating symbols of FIG. 3, and assuming that the second scale of the arrangement designating symbol of FIG. 5 is one scale of that of FIG. 3, it is as shown in FIG. It will be arranged.

[0011]

As described above, according to the present invention, since the placement instruction symbol is applied to the placement of the function macro and the leaf cells of the lower hierarchy, the ease of performing the placement operation is provided. There is no need to pay attention to even the finest parts, the effort of attribute input is saved, the layout information on the layout can be adjusted easily, and the layout operation is not limited by the size of the symbol. Have a result.

[Brief description of drawings]

FIG. 1 is a flow chart of an embodiment of the present invention.

FIG. 2 shows the contents of the register transfer circuit schematic file shown in FIG.

FIG. 3 shows the contents of the register transfer layout diagram file shown in FIG.

FIG. 4 shows the contents of the library circuit diagram file shown in FIG.

FIG. 5 shows the contents of the library circuit layout file shown in FIG.

FIG. 6 is a cell placement result of the embodiment shown in FIG.

FIG. 7 is a flowchart of a conventional technique.

FIG. 8 is a diagram in which FIGS. 2, 3, and 6 are on the same page.

[Explanation of symbols]

 101 register transfer schematic file 102, 106 layout editing 103 register transfer layout file 104 relative position detection 105 library circuit layout file 107 library schematic file 108 hierarchy expansion 109 position detection 110 leaf cell layout file 111, 702 cell layout result file 201 to 204 Function macro 205 Origin of symbol 301 Placement instruction symbols 401 to 404, 601 to 616 Leaf cell 701 Manual editing

Claims (1)

[Claims] 1. A data path compiler, which is an automatic layout tool for a data path section, includes placement information obtained by placing a function macro symbol on a register transfer level circuit diagram between placement instruction symbols, and a function macro of the function macro. An arrangement system characterized in that the cell arrangement information of the entire data path is determined by hierarchically expanding by referring to the arrangement information obtained by arranging the lower layer leaf cell symbols in the arrangement instruction symbols of different scales.