Make global placement output less mysterious

[oharboe]

Description

The global placement logging is a bit mysterious and hard to read.

I was trying to see if I could find in the log a recommendation for the highest viable placement density.

[INFO ORD-0030] Using 48 thread(s).
global_placement -density 0.82 -pad_left 0 -pad_right 0 -routability_driven -timing_driven
[INFO GPL-0002] DBU: 1000
[INFO GPL-0003] SiteSize: (  0.054  0.270 ) um
[INFO GPL-0004] CoreBBox: (  1.080  1.080 ) ( 42.120 42.120 ) um
[INFO GPL-0006] NumInstances:              3735
[INFO GPL-0007] NumPlaceInstances:         3354
[INFO GPL-0008] NumFixedInstances:          381
[INFO GPL-0009] NumDummyInstances:            0
[INFO GPL-0010] NumNets:                   3906
[INFO GPL-0011] NumPins:                  10296
[INFO GPL-0012] DieBBox:  (  0.000  0.000 ) ( 43.200 43.200 ) um
[INFO GPL-0013] CoreBBox: (  1.080  1.080 ) ( 42.120 42.120 ) um
[INFO GPL-0016] CoreArea:              1684.282 um^2
[INFO GPL-0017] NonPlaceInstsArea:       11.110 um^2
[INFO GPL-0018] PlaceInstsArea:         447.854 um^2
[INFO GPL-0019] Util:                    26.767 %
[INFO GPL-0020] StdInstsArea:           447.854 um^2
[INFO GPL-0021] MacroInstsArea:           0.000 um^2
[InitialPlace]  Iter: 1 CG residual: 0.00000455 HPWL: 14522824
[InitialPlace]  Iter: 2 CG residual: 0.00000073 HPWL: 8033894
[InitialPlace]  Iter: 3 CG residual: 0.00000035 HPWL: 8174271
[InitialPlace]  Iter: 4 CG residual: 0.00000030 HPWL: 8186618
[InitialPlace]  Iter: 5 CG residual: 0.00000031 HPWL: 8192909
[INFO GPL-0031] FillerInit:NumGCells:     10484
[INFO GPL-0032] FillerInit:NumGNets:       3906
[INFO GPL-0033] FillerInit:NumGPins:      10296
[INFO GPL-0023] TargetDensity:            0.820
[INFO GPL-0024] AvrgPlaceInstArea:        0.134 um^2
[INFO GPL-0025] IdealBinArea:             0.163 um^2
[INFO GPL-0026] IdealBinCnt:              10343
[INFO GPL-0027] TotalBinArea:          1684.282 um^2
[INFO GPL-0028] BinCnt:        64     64
[INFO GPL-0029] BinSize: (  0.642  0.642 )
[INFO GPL-0030] NumBins: 4096
[NesterovSolve] Iter:    1 overflow: 0.572 HPWL: 5902357
[INFO GPL-0100] Timing-driven iteration 1/6, virtual: true.
[INFO GPL-0101] Iter: 0, overflow: 0.572, keep rsz at: 0.3
[INFO GPL-0106] Timing-driven: worst slack -1.23e-12
[INFO GPL-0103] Timing-driven: weighted 368 nets.
[NesterovSolve] Snapshot saved at iter = 0
[NesterovSolve] Iter:   10 overflow: 0.584 HPWL: 5292944
[NesterovSolve] Iter:   20 overflow: 0.578 HPWL: 5364395
[NesterovSolve] Iter:   30 overflow: 0.570 HPWL: 5457854
[NesterovSolve] Iter:   40 overflow: 0.564 HPWL: 5526983
[NesterovSolve] Iter:   50 overflow: 0.563 HPWL: 5550340
[NesterovSolve] Iter:   60 overflow: 0.565 HPWL: 5537153
[NesterovSolve] Iter:   70 overflow: 0.566 HPWL: 5525718
[NesterovSolve] Iter:   80 overflow: 0.566 HPWL: 5524165
[NesterovSolve] Iter:   90 overflow: 0.564 HPWL: 5531882
[NesterovSolve] Iter:  100 overflow: 0.560 HPWL: 5543918
[NesterovSolve] Iter:  110 overflow: 0.554 HPWL: 5563355
[NesterovSolve] Iter:  120 overflow: 0.542 HPWL: 5580553
[NesterovSolve] Iter:  130 overflow: 0.526 HPWL: 5588766
[NesterovSolve] Iter:  140 overflow: 0.509 HPWL: 5579037
[INFO GPL-0100] Timing-driven iteration 2/6, virtual: true.
[INFO GPL-0101] Iter: 148, overflow: 0.484, keep rsz at: 0.3
[INFO GPL-0106] Timing-driven: worst slack -1.78e-12
[INFO GPL-0103] Timing-driven: weighted 369 nets.
[NesterovSolve] Iter:  150 overflow: 0.482 HPWL: 5544295
[NesterovSolve] Iter:  160 overflow: 0.458 HPWL: 5502705
[NesterovSolve] Iter:  170 overflow: 0.422 HPWL: 5519045
[NesterovSolve] Iter:  180 overflow: 0.386 HPWL: 5526755
[NesterovSolve] Iter:  190 overflow: 0.347 HPWL: 5572882
[NesterovSolve] Iter:  200 overflow: 0.315 HPWL: 5565735
[INFO GPL-0075] Routability iteration: 1
[INFO GPL-0036] TileBBox: (    0    0 ) (  540  540 ) DBU
[INFO GPL-0038] TileCnt:      80   80
[INFO GPL-0040] NumTiles: 6400
[INFO GPL-0081] TotalRouteOverflow: 0.0000
[INFO GPL-0082] OverflowTileCnt: 0
[INFO GPL-0083] 0.5%RC: 0.9062
[INFO GPL-0084] 1.0%RC: 0.8817
[INFO GPL-0085] 2.0%RC: 0.8512
[INFO GPL-0086] 5.0%RC: 0.8021
[INFO GPL-0087] FinalRC: 0.89392096
[INFO GPL-0077] FinalRC lower than targetRC(1.0100), routability not needed.
[NesterovSolve] Iter:  210 overflow: 0.289 HPWL: 5564780
[INFO GPL-0100] Timing-driven iteration 3/6, virtual: false.
[INFO GPL-0101] Iter: 211, overflow: 0.282, keep rsz at: 0.3
[INFO GPL-0106] Timing-driven: worst slack -4.92e-12
[INFO GPL-0103] Timing-driven: weighted 369 nets.
[INFO GPL-0107] Timing-driven: repair_design delta area: 30.808 um^2 (+6.88%)
[INFO GPL-0108] Timing-driven: new target density: 0.83841264
[NesterovSolve] Iter:  220 overflow: 0.261 HPWL: 3775141
[NesterovSolve] Iter:  230 overflow: 0.228 HPWL: 3609155
[INFO GPL-0100] Timing-driven iteration 4/6, virtual: false.
[INFO GPL-0101] Iter: 234, overflow: 0.204, keep rsz at: 0.3
[INFO GPL-0106] Timing-driven: worst slack -7.07e-12
[INFO GPL-0103] Timing-driven: weighted 369 nets.
[INFO GPL-0107] Timing-driven: repair_design delta area: 2.887 um^2 (+0.60%)
[INFO GPL-0108] Timing-driven: new target density: 0.84013796
[NesterovSolve] Iter:  240 overflow: 0.195 HPWL: 3414992
[NesterovSolve] Iter:  250 overflow: 0.165 HPWL: 3365317
[INFO GPL-0100] Timing-driven iteration 5/6, virtual: false.
[INFO GPL-0101] Iter: 258, overflow: 0.144, keep rsz at: 0.3
[INFO GPL-0106] Timing-driven: worst slack -5.28e-12
[INFO GPL-0103] Timing-driven: weighted 367 nets.
[INFO GPL-0107] Timing-driven: repair_design delta area: -0.408 um^2 (-0.08%)
[INFO GPL-0108] Timing-driven: new target density: 0.839894
[NesterovSolve] Iter:  260 overflow: 0.142 HPWL: 3311617
[NesterovSolve] Iter:  270 overflow: 0.124 HPWL: 3243999
[NesterovSolve] Iter:  280 overflow: 0.103 HPWL: 3224978
[NesterovSolve] Finished with Overflow: 0.097642

Suggested Solution

Suggestions:

Noise? Make it debug info:

[INFO GPL-0002] DBU: 1000

There's enough horizontal space to spell out CG and HPWL:

[InitialPlace]  Iter: 1 CG residual: 0.00000455 HPWL: 14522824

What is a "GCell", "GNets", "GPins"? There is enough horizontal space to spell it out:

[INFO GPL-0031] FillerInit:NumGCells:     10484
[INFO GPL-0032] FillerInit:NumGNets:       3906
[INFO GPL-0033] FillerInit:NumGPins:      10296

Spell out "Placement target density: "

[INFO GPL-0023] TargetDensity:            0.820

More human friendly and easier to read, spell out, e.g. "Average placement instance area: "

[INFO GPL-0024] AvrgPlaceInstArea:        0.134 um^2
[INFO GPL-0025] IdealBinArea:             0.163 um^2
[INFO GPL-0026] IdealBinCnt:              10343
[INFO GPL-0027] TotalBinArea:          1684.282 um^2
[INFO GPL-0028] BinCnt:        64     64
[INFO GPL-0029] BinSize: (  0.642  0.642 )
[INFO GPL-0030] NumBins: 4096

Spell out "rsz":

[INFO GPL-0101] Iter: 0, overflow: 0.572, keep rsz at: 0.3

Debug information?

[INFO GPL-0103] Timing-driven: weighted 369 nets.

Debug info? If needed, print once, not every time:

[INFO GPL-0036] TileBBox: (    0    0 ) (  540  540 ) DBU
[INFO GPL-0038] TileCnt:      80   80
[INFO GPL-0040] NumTiles: 6400

Spell out to make it easier to read and understand, there is enough space horizontally:

[INFO GPL-0081] TotalRouteOverflow: 0.0000
[INFO GPL-0082] OverflowTileCnt: 0
[INFO GPL-0083] 0.5%RC: 0.9062
[INFO GPL-0084] 1.0%RC: 0.8817
[INFO GPL-0085] 2.0%RC: 0.8512
[INFO GPL-0086] 5.0%RC: 0.8021
[INFO GPL-0087] FinalRC: 0.89392096
[INFO GPL-0077] FinalRC lower than targetRC(1.0100), routability not needed.

Additional Context

No response