odb: Crash on `dbInsertBuffer::stitchLoadToDriver()`

[jhkim-pii]

Describe the bug

Crash occurred during dbInsertBuffer::stitchLoadToDriver() execution in CTS stage when SWAP_ARITH_OPERATORS=1.

Design: gf12/ca53

Log

flow$ make DESIGN_CONFIG=./designs/gf12/ca53/config.mk OPENROAD_HIERARCHICAL=1 SWAP_ARITH_OPERATORS=1 all

...
[2026-01-30T09:50:55.971Z] [INFO CTS-0124] Clock net "u_ca53_noram\/u_ca53dpu\/u_dpu_dp\/u_alu1\/clk_ex2_regs"
[2026-01-30T09:50:55.971Z] [INFO CTS-0125]  Sinks 1
[2026-01-30T09:50:55.971Z] [INFO CTS-0124] Clock net "u_ca53_noram\/u_ca53dpu\/u_dpu_br\/clk_br_ex2_regs"
[2026-01-30T09:50:55.971Z] [INFO CTS-0125]  Sinks 1
[2026-01-30T09:50:55.971Z] [INFO CTS-0124] Clock net "u_ca53_noram\/u_ca53dpu\/u_dpu_br\/clk_br_ex1_regs"
[2026-01-30T09:50:55.971Z] [INFO CTS-0125]  Sinks 1
[2026-01-30T09:51:45.137Z] [INFO RSZ-0047] Found 55 long wires.
[2026-01-30T09:51:45.137Z] [INFO RSZ-0048] Inserted 145 buffers in 55 nets.
[2026-01-30T09:51:45.137Z] [INFO CTS-0033] Balancing latency for clock clk
[2026-01-30T09:52:01.907Z] Signal 11 received
[2026-01-30T09:52:01.907Z] Stack trace:
[2026-01-30T09:52:01.907Z]  0# 0x00005CAECD8484B7 in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z]  1# 0x000072E123442520 in /lib/x86_64-linux-gnu/libc.so.6
[2026-01-30T09:52:01.907Z]  2# odb::dbInsertBuffer::stitchLoadToDriver(odb::dbITerm*, odb::dbITerm*, std::set<odb::dbObject*, std::less<odb::dbObject*>, std::allocator<odb::dbObject*> > const&) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z]  3# odb::dbInsertBuffer::rewireBufferLoadPins(std::set<odb::dbObject*, std::less<odb::dbObject*>, std::allocator<odb::dbObject*> > const&) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z]  4# odb::dbInsertBuffer::insertBufferBeforeLoads(std::set<odb::dbObject*, std::less<odb::dbObject*>, std::allocator<odb::dbObject*> > const&, odb::dbMaster const*, odb::Point const*, char const*, char const*, odb::dbNameUniquifyType const&, bool) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z]  5# odb::dbNet::insertBufferBeforeLoads(std::set<odb::dbObject*, std::less<odb::dbObject*>, std::allocator<odb::dbObject*> > const&, odb::dbMaster const*, odb::Point const*, char const*, char const*, odb::dbNameUniquifyType const&, bool) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z]  6# cts::LatencyBalancer::insertDelayBuffers(int, int, int, std::vector<odb::dbITerm*, std::allocator<odb::dbITerm*> > const&) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z]  7# cts::LatencyBalancer::balanceLatencies(int) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z]  8# cts::LatencyBalancer::balanceLatencies(int) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z]  9# cts::LatencyBalancer::balanceLatencies(int) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 10# cts::LatencyBalancer::balanceLatencies(int) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 11# cts::LatencyBalancer::balanceLatencies(int) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 12# cts::LatencyBalancer::balanceLatencies(int) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 13# cts::LatencyBalancer::balanceLatencies(int) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 14# cts::LatencyBalancer::balanceLatencies(int) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 15# cts::LatencyBalancer::balanceLatencies(int) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 16# cts::LatencyBalancer::balanceLatencies(int) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 17# cts::LatencyBalancer::balanceLatencies(int) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 18# cts::LatencyBalancer::balanceLatencies(int) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 19# cts::LatencyBalancer::balanceLatencies(int) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 20# cts::LatencyBalancer::balanceLatencies(int) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 21# cts::LatencyBalancer::balanceLatencies(int) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 22# cts::LatencyBalancer::balanceLatencies(int) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 23# cts::LatencyBalancer::balanceLatencies(int) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 24# cts::LatencyBalancer::balanceLatencies(int) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 25# cts::LatencyBalancer::balanceLatencies(int) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 26# cts::LatencyBalancer::balanceLatencies(int) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 27# cts::LatencyBalancer::run() in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 28# cts::TritonCTS::balanceMacroRegisterLatencies() in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 29# cts::TritonCTS::runTritonCts() in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 30# 0x00005CAECDD882B5 in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 31# TclNRRunCallbacks in /lib/x86_64-linux-gnu/libtcl8.6.so
[2026-01-30T09:52:01.907Z] 32# 0x000072E12813B028 in /lib/x86_64-linux-gnu/libtcl8.6.so
[2026-01-30T09:52:01.907Z] 33# Tcl_EvalEx in /lib/x86_64-linux-gnu/libtcl8.6.so
[2026-01-30T09:52:01.907Z] 34# Tcl_Eval in /lib/x86_64-linux-gnu/libtcl8.6.so
[2026-01-30T09:52:01.907Z] 35# sta::sourceTclFile(char const*, bool, bool, Tcl_Interp*) in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 36# 0x00005CAECFE5BEBB in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 37# Tcl_MainEx in /lib/x86_64-linux-gnu/libtcl8.6.so
[2026-01-30T09:52:01.907Z] 38# main in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] 39# 0x000072E123429D90 in /lib/x86_64-linux-gnu/libc.so.6
[2026-01-30T09:52:01.907Z] 40# __libc_start_main in /lib/x86_64-linux-gnu/libc.so.6
[2026-01-30T09:52:01.907Z] 41# _start in /tmp/workspace/secure-fix-replace-arith-modules/tools/install/OpenROAD/bin/openroad
[2026-01-30T09:52:01.907Z] Command terminated by signal 11
[2026-01-30T09:52:01.907Z] Elapsed time: 3:31.50[h:]min:sec. CPU time: user 336.84 sys 149.18 (229%). Peak memory: 4599160KB.
[2026-01-30T09:52:01.907Z] make[1]: *** [Makefile:507: do-4_1_cts] Error 1
[2026-01-30T09:52:01.907Z] make: *** [Makefile:507: results/gf12/ca53_cpu/base/4_1_cts.odb] Error 2

Expected Behavior

No crash.

Environment

-- OpenROAD version: 26Q1-745-g4f93607760
-- System name: Linux
-- Compiler: GNU 13.3.0
-- Build type: RelWithDebInfo
-- Install prefix: /workspace/ws7/OpenROAD-flow-scripts/tools/install/OpenROAD
-- C++ Standard: 20
-- C++ Standard Required: ON
-- C++ Extensions: OFF
-- LTO/IPO is disabled
-- Performing Test C_COMPILER_SUPPORTS__-std=c++17
-- Performing Test C_COMPILER_SUPPORTS__-std=c++17 - Failed
-- Performing Test CXX_COMPILER_SUPPORTS__-std=c++17
-- Performing Test CXX_COMPILER_SUPPORTS__-std=c++17 - Success
-- TCL library: /usr/lib/x86_64-linux-gnu/libtcl.so
-- TCL header: /usr/include/tcl/tcl.h
-- TCL readline library: /usr/lib/x86_64-linux-gnu/libtclreadline.so
-- TCL readline header: /usr/include/x86_64-linux-gnu
-- Found SWIG: /usr/local/bin/swig (found suitable version "4.3.0", minimum required is "4.0")
-- Using SWIG >= 4.3.0 -flatstaticmethod flag for python
-- boost: 1.89.0
-- GTest: 1.13.0
-- spdlog: 1.15.0
-- STA version: 2.7.0
-- STA git sha: 087793e8a0c0245d0b696039c638acad425fbf66
-- System name: Linux
-- Compiler: GNU 13.3.0
-- Build type: RelWithDebInfo
-- Build CXX_FLAGS: 
-- Install prefix: /workspace/ws7/OpenROAD-flow-scripts/tools/install/OpenROAD
-- TCL library: /usr/lib/x86_64-linux-gnu/libtcl.so
-- TCL header: /usr/include/tcl/tcl.h
-- TCL readline library: /usr/lib/x86_64-linux-gnu/libtclreadline.so
-- TCL readline header: /usr/include/x86_64-linux-gnu/tclreadline.h
-- CUDD library: /usr/local/lib/libcudd.a
-- CUDD header: /usr/local/include/cudd.h
-- SSTA: 0
-- Found SWIG: /usr/local/bin/swig (found suitable version "4.3.0", minimum required is "3.0")
-- STA library: /workspace/ws7/OpenROAD-flow-scripts/tools/OpenROAD/build/libOpenSTA.a
-- STA executable: /workspace/ws7/OpenROAD-flow-scripts/tools/OpenROAD/build/sta
-- Found OR-Tools: /opt/or-tools/lib/cmake/ortools (version: 9.11.4210)
-- TCL library: /usr/lib/x86_64-linux-gnu/libtcl.so
-- TCL header: /usr/include/tcl/tcl.h
-- Found OpenMP: TRUE (found version "4.5")
-- Found OpenMP: TRUE (found version "4.5")
-- GUI is enabled
-- Could NOT find VTune (missing: VTune_LIBRARIES VTune_INCLUDE_DIRS) 
-- TCL library: /usr/lib/x86_64-linux-gnu/libtcl.so
-- TCL header: /usr/include/tcl/tcl.h
-- TCL readline enabled
-- Tcl Extended disabled
-- Python3 enabled

To Reproduce

flow$ make DESIGN_CONFIG=./designs/gf12/ca53/config.mk OPENROAD_HIERARCHICAL=1 SWAP_ARITH_OPERATORS=1 all

Relevant log output

Screenshots

No response

Additional Context

No response