From e53dc758fd8b85e0b0b97f230f965c87fec49e7f Mon Sep 17 00:00:00 2001
From: clc5q <clc5q@git.zephyr-software.com>
Date: Thu, 25 Sep 2014 15:36:16 +0000
Subject: [PATCH] Handle fast return suppression on tail call cases.
---
SMPDataFlowAnalysis.cpp | 2 ++
SMPFunction.cpp | 8 ++++++++
SMPFunction.h | 3 ++-
SMPInstr.cpp | 5 +++++
SMPProgram.cpp | 12 +++++++-----
5 files changed, 24 insertions(+), 6 deletions(-)
diff --git a/SMPDataFlowAnalysis.cpp b/SMPDataFlowAnalysis.cpp
index b4cdb0b6..db842c2e 100644
--- a/SMPDataFlowAnalysis.cpp
+++ b/SMPDataFlowAnalysis.cpp
@@ -3200,8 +3200,10 @@ SMPOperandType SMPPhiFunction::ConditionalMeetType(SMPBasicBlock *CurrBlock) con
if ((BADADDR != DefAddr) && (DefAddr >= CurrBlock->GetFunc()->GetFirstFuncAddr())) {
SMPInstr *DefInst = CurrBlock->GetFunc()->GetInstFromAddr(DefAddr);
set<DefOrUse, LessDefUse>::iterator DefIter = DefInst->SetDefType(PhiOp, PtrType);
+#if 0
SMP_msg("INFO: Converting zeroed reg from NUMERIC to POINTER at %lx for Block at %lx\n",
(unsigned long) DefAddr, (unsigned long) BlockStartAddr);
+#endif
CurrBlock->GetFunc()->ResetProcessedBlocks();
SMPBasicBlock *DefBlock = CurrBlock->GetFunc()->GetBlockFromInstAddr(DefAddr);
#if 0 // Causes infinite loops, crashes; need to debug !!!!****!!!!
diff --git a/SMPFunction.cpp b/SMPFunction.cpp
index 5875d0fa..48bffd01 100644
--- a/SMPFunction.cpp
+++ b/SMPFunction.cpp
@@ -8619,6 +8619,7 @@ void SMPFunction::MarkFunctionSafe() {
bool HasIndirectWrite = false;
bool IsIndirectCallTarget = false; // could be called indirectly
bool IsTailCallTarget = false; // could be called by jump instruction used as tail call
+ bool MakesTailCall = false; // problem for Fast Returns, not fo return address safety
bool HasNoCallers = this->AllCallSources.empty();
this->ReturnAddrStatus = FUNC_SAFE;
@@ -8730,6 +8731,9 @@ void SMPFunction::MarkFunctionSafe() {
}
continue;
}
+ if ((CurrInst->IsTailCall()) || (CurrInst->IsCondTailCall())) {
+ MakesTailCall = true;
+ }
if (CurrInst->MDIsPopInstr() || CurrInst->MDIsReturnInstr()) {
// ignore pops and returns for the moment
continue;
@@ -8868,6 +8872,10 @@ void SMPFunction::MarkFunctionSafe() {
SMP_msg("INFO: Function at %lx becoming unsafe for fast returns because it has no callers.\n", (unsigned long) this->FirstEA);
this->SetUnsafeForFastReturns(true, NO_CALLERS);
}
+ if (MakesTailCall) {
+ SMP_msg("INFO: Function at %lx becoming unsafe for fast returns because it makes a tail call.\n", (unsigned long) this->FirstEA);
+ this->SetUnsafeForFastReturns(true, MAKES_TAIL_CALL);
+ }
if (UnsafeReturnAddr) {
SMP_msg("INFO: Function at %lx becoming unsafe for fast returns because its return addr is UNSAFE.\n", (unsigned long) this->FirstEA);
diff --git a/SMPFunction.h b/SMPFunction.h
index 8fdbeaaa..26b7d31d 100644
--- a/SMPFunction.h
+++ b/SMPFunction.h
@@ -120,7 +120,8 @@ enum UnsafeFastReturnReason {
INDIRECTLY_CALLED = 8,
NO_CALLERS = 16,
TAIL_CALL_TARGET = 32,
- RAUNSAFE_CALLEES = 64
+ RAUNSAFE_CALLEES = 64,
+ MAKES_TAIL_CALL = 128
};
enum ControlFlowType {
diff --git a/SMPInstr.cpp b/SMPInstr.cpp
index b19fbc6f..a7daf19e 100644
--- a/SMPInstr.cpp
+++ b/SMPInstr.cpp
@@ -9682,6 +9682,9 @@ void SMPInstr::EmitFastReturnStatus(unsigned short FastReturnStatus) {
if (TAIL_CALL_TARGET & FastReturnStatus) {
SMP_fprintf(STARS_CallReturnFile, "TAILCALLED ");
}
+ if (MAKES_TAIL_CALL & FastReturnStatus) {
+ SMP_fprintf(STARS_CallReturnFile, "MAKES_TAIL_CALL ");
+ }
if (RAUNSAFE_CALLEES & FastReturnStatus) {
SMP_fprintf(STARS_CallReturnFile, "UNSAFE_CALLEES ");
}
@@ -10552,6 +10555,8 @@ void SMPInstr::EmitIntegerErrorAnnotations(FILE *InfoAnnotFile, list<size_t> &Lo
SSANum = DefIter->GetSSANum();
SMPOperandType DefType = DefIter->GetType();
SMPOperandType MemType;
+ SMPMetadataType DefMetaStatus = DefIter->GetMetadataStatus();
+ bool DefUnusedMetadata = (DEF_METADATA_UNUSED == DefMetaStatus);
bool IgnoreOverflow = this->IsBenignOverflow(IdiomCode);
uval_t ConstValue = 0;
// NOTE: We no longer suppress the IgnoreOverflow annotations. Instead, we print
diff --git a/SMPProgram.cpp b/SMPProgram.cpp
index 564d62aa..60f5debb 100644
--- a/SMPProgram.cpp
+++ b/SMPProgram.cpp
@@ -746,18 +746,20 @@ void SMPProgram::Analyze(ProfilerInformation *pi) {
if (CurrFunc->StackPtrAnalysisSucceeded() && CurrFunc->HasGoodRTLs() && !CurrFunc->HasIndirectJumps() && !CurrFunc->HasSharedChunks()) {
#endif
changed |= CurrFunc->InferInterproceduralTypes();
+ }
#if 0
- if (0 == strcmp("__mktime_internal", CurrFunc->GetFuncName())) {
- CurrFunc->Dump();
- }
-#endif
+ if ((!changed || (IterationCounter > STARS_INTERPROCEDURAL_ITERATION_LIMIT)) && (0 == strcmp("__mktime_internal", CurrFunc->GetFuncName()))) {
+ CurrFunc->Dump();
}
+#endif
}
} while (changed && (IterationCounter <= STARS_INTERPROCEDURAL_ITERATION_LIMIT));
SMP_msg("Interprocedural type inference terminated after iteration %zu changed: %d\n", IterationCounter, changed);
#endif
- // Free memory not needed to emit annotations, now that type inference is done.
+
+
+ // Free memory not needed to emit annotations, now that type inference is done.
CurrFunc->FreeUnusedMemory4();
#if SMP_COUNT_MEMORY_ALLOCATIONS
--
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