[llvm] 623295a - [MISched][scheduleDump] Use stable_sort to prevent test failures.

[Francesco Petrogalli via llvm-commits]

Author: Francesco Petrogalli
Date: 2023-06-13T14:40:29+02:00
New Revision: 623295a1d0cc8d0ace354b1b97959df49be8a86e

URL: https://github.com/llvm/llvm-project/commit/623295a1d0cc8d0ace354b1b97959df49be8a86e
DIFF: https://github.com/llvm/llvm-project/commit/623295a1d0cc8d0ace354b1b97959df49be8a86e.diff

LOG: [MISched][scheduleDump] Use stable_sort to prevent test failures.

When building the compiler with -DLLVM_ENABLE_EXPENSIVE_CHECKS=ON,
sometimes resources that are dumped in scheduled traces gets reordered
even if they are booked in the same cycle. Using `stable_sort`
guarantees that such occasional reordering does not happen.

This change should fix failures like the one seen in
https://lab.llvm.org/buildbot/#/builders/16/builds/49592.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D152800

Added: 
    

Modified: 
    llvm/lib/CodeGen/MachineScheduler.cpp

Removed: 
    


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diff  --git a/llvm/lib/CodeGen/MachineScheduler.cpp b/llvm/lib/CodeGen/MachineScheduler.cpp
index b41b2d83f01c4..28b17f76c99e2 100644
--- a/llvm/lib/CodeGen/MachineScheduler.cpp
+++ b/llvm/lib/CodeGen/MachineScheduler.cpp
@@ -1010,13 +1010,13 @@ LLVM_DUMP_METHOD void ScheduleDAGMI::dumpScheduleTraceTopDown() const {
                    SchedModel.getWriteProcResEnd(SC)));
 
     if (MISchedSortResourcesInTrace)
-      llvm::sort(ResourcesIt.begin(), ResourcesIt.end(),
-                 [](const MCWriteProcResEntry &LHS,
-                    const MCWriteProcResEntry &RHS) -> bool {
-                   return LHS.StartAtCycle < RHS.StartAtCycle ||
-                          (LHS.StartAtCycle == RHS.StartAtCycle &&
-                           LHS.Cycles < RHS.Cycles);
-                 });
+      llvm::stable_sort(ResourcesIt,
+                        [](const MCWriteProcResEntry &LHS,
+                           const MCWriteProcResEntry &RHS) -> bool {
+                          return LHS.StartAtCycle < RHS.StartAtCycle ||
+                                 (LHS.StartAtCycle == RHS.StartAtCycle &&
+                                  LHS.Cycles < RHS.Cycles);
+                        });
     for (const MCWriteProcResEntry &PI : ResourcesIt) {
       C = FirstCycle;
       const std::string ResName =
@@ -1090,13 +1090,13 @@ LLVM_DUMP_METHOD void ScheduleDAGMI::dumpScheduleTraceBottomUp() const {
                    SchedModel.getWriteProcResEnd(SC)));
 
     if (MISchedSortResourcesInTrace)
-      llvm::sort(ResourcesIt.begin(), ResourcesIt.end(),
-                 [](const MCWriteProcResEntry &LHS,
-                    const MCWriteProcResEntry &RHS) -> bool {
-                   return LHS.StartAtCycle < RHS.StartAtCycle ||
-                          (LHS.StartAtCycle == RHS.StartAtCycle &&
-                           LHS.Cycles < RHS.Cycles);
-                 });
+      llvm::stable_sort(ResourcesIt,
+                        [](const MCWriteProcResEntry &LHS,
+                           const MCWriteProcResEntry &RHS) -> bool {
+                          return LHS.StartAtCycle < RHS.StartAtCycle ||
+                                 (LHS.StartAtCycle == RHS.StartAtCycle &&
+                                  LHS.Cycles < RHS.Cycles);
+                        });
     for (const MCWriteProcResEntry &PI : ResourcesIt) {
       C = FirstCycle;
       const std::string ResName =