AsmMatcherEmitter: Use stable_sort when reordering instructions, so that order
is still deterministic even amongst ambiguous instructions (eventually ambiguous
match orders will be a hard error, but we aren't there yet).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95157 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/utils/TableGen/AsmMatcherEmitter.cpp b/utils/TableGen/AsmMatcherEmitter.cpp
index dca7929..c80285f 100644
--- a/utils/TableGen/AsmMatcherEmitter.cpp
+++ b/utils/TableGen/AsmMatcherEmitter.cpp
@@ -1413,9 +1413,11 @@
AsmMatcherInfo Info(AsmParser);
Info.BuildInfo(Target);
- // Sort the instruction table using the partial order on classes.
- std::sort(Info.Instructions.begin(), Info.Instructions.end(),
- less_ptr<InstructionInfo>());
+ // Sort the instruction table using the partial order on classes. We use
+ // stable_sort to ensure that ambiguous instructions are still
+ // deterministically ordered.
+ std::stable_sort(Info.Instructions.begin(), Info.Instructions.end(),
+ less_ptr<InstructionInfo>());
DEBUG_WITH_TYPE("instruction_info", {
for (std::vector<InstructionInfo*>::iterator