Replace DelayInfo with DelayPair/DelayQuad

This replaces the arch-specific DelayInfo structure with new DelayPair
(min/max only) and DelayQuad (min/max for both rise and fall) structures
that form part of common code.

This further reduces the amount of arch-specific code; and also provides
useful data structures for timing analysis which will need to delay
with pairs/quads of delays as it is improved.

While there may be a small performance cost to arches that didn't
separate the rise/fall cases (arches that aren't currently separating
the min/max cases just need to be fixed...) in DelayInfo, my expectation
is that inlining will mean this doesn't make much difference.

Signed-off-by: gatecat <gatecat@ds0.me>

3 files changed, 5 insertions, 36 deletions

diff --git a/fpga_interchange/arch.cc b/fpga_interchange/arch.cc
index 71ba46e4..9bcd7f79 100644
--- a/fpga_interchange/arch.cc
+++ b/fpga_interchange/arch.cc
@@ -686,7 +686,7 @@ delay_t Arch::predictDelay(const NetInfo *net_info, const PortRef &sink) const
     return 0;
 }
 
-bool Arch::getCellDelay(const CellInfo *cell, IdString fromPort, IdString toPort, DelayInfo &delay) const
+bool Arch::getCellDelay(const CellInfo *cell, IdString fromPort, IdString toPort, DelayQuad &delay) const
 {
     // FIXME: Implement when adding timing-driven place and route.
     return false;
diff --git a/fpga_interchange/arch.h b/fpga_interchange/arch.h
index 76497d6d..82a2788b 100644
--- a/fpga_interchange/arch.h
+++ b/fpga_interchange/arch.h
@@ -1127,12 +1127,7 @@ struct Arch : ArchAPI<ArchRanges>
         return w2n == wire_to_net.end() ? nullptr : w2n->second;
     }
 
-    DelayInfo getWireDelay(WireId wire) const override
-    {
-        DelayInfo delay;
-        delay.delay = 0;
-        return delay;
-    }
+    DelayQuad getWireDelay(WireId wire) const override { return DelayQuad(0); }
 
     TileWireRange get_tile_wire_range(WireId wire) const
     {
@@ -1279,7 +1274,7 @@ struct Arch : ArchAPI<ArchRanges>
         return canonical_wire(chip_info, pip.tile, loc_info(chip_info, pip).pip_data[pip.index].dst_index);
     }
 
-    DelayInfo getPipDelay(PipId pip) const override { return DelayInfo(); }
+    DelayQuad getPipDelay(PipId pip) const override { return DelayQuad(0); }
 
     DownhillPipRange getPipsDownhill(WireId wire) const override
     {
@@ -1333,12 +1328,7 @@ struct Arch : ArchAPI<ArchRanges>
     delay_t getDelayEpsilon() const override { return 20; }
     delay_t getRipupDelayPenalty() const override { return 120; }
     float getDelayNS(delay_t v) const override { return v * 0.001; }
-    DelayInfo getDelayFromNS(float ns) const override
-    {
-        DelayInfo del;
-        del.delay = delay_t(ns * 1000);
-        return del;
-    }
+    delay_t getDelayFromNS(float ns) const override { return delay_t(ns * 1000); }
     uint32_t getDelayChecksum(delay_t v) const override { return v; }
     bool getBudgetOverride(const NetInfo *net_info, const PortRef &sink, delay_t &budget) const override;
 
@@ -1363,7 +1353,7 @@ struct Arch : ArchAPI<ArchRanges>
 
     // Get the delay through a cell from one port to another, returning false
     // if no path exists. This only considers combinational delays, as required by the Arch API
-    bool getCellDelay(const CellInfo *cell, IdString fromPort, IdString toPort, DelayInfo &delay) const override;
+    bool getCellDelay(const CellInfo *cell, IdString fromPort, IdString toPort, DelayQuad &delay) const override;
     // Get the port class, also setting clockInfoCount to the number of TimingClockingInfos associated with a port
     TimingPortClass getPortTimingClass(const CellInfo *cell, IdString port, int &clockInfoCount) const override;
     // Get the TimingClockingInfo of a port
diff --git a/fpga_interchange/archdefs.h b/fpga_interchange/archdefs.h
index e280de55..75af6974 100644
--- a/fpga_interchange/archdefs.h
+++ b/fpga_interchange/archdefs.h
@@ -28,27 +28,6 @@ NEXTPNR_NAMESPACE_BEGIN
 
 typedef int delay_t;
 
-struct DelayInfo
-{
-    delay_t delay = 0;
-
-    delay_t minRaiseDelay() const { return delay; }
-    delay_t maxRaiseDelay() const { return delay; }
-
-    delay_t minFallDelay() const { return delay; }
-    delay_t maxFallDelay() const { return delay; }
-
-    delay_t minDelay() const { return delay; }
-    delay_t maxDelay() const { return delay; }
-
-    DelayInfo operator+(const DelayInfo &other) const
-    {
-        DelayInfo ret;
-        ret.delay = this->delay + other.delay;
-        return ret;
-    }
-};
-
 // -----------------------------------------------------------------------
 
 struct BelId