RPCS3/llvm
1
0
Fork 0
mirror of https://github.com/RPCS3/llvm.git synced 2025-01-22 02:05:01 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

Fix reassociate to postpone certain instruction deletions until

Browse Source 
after it has finished all of its reassociations, because its
habit of unlinking operands and holding them in a datastructure
while working means that it's not easy to determine when an
instruction is really dead until after all its regular work is
done. rdar://9096268.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127424 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Dan Gohman 2011-03-10 19:51:54 +00:00
parent a4f809d8db
commit fa0e6facc7
2 changed files with 36 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
lib/Transforms/Scalar/Reassociate.cpp
View File

@ -22,6 +22,7 @@
#define DEBUG_TYPE "reassociate"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Function.h"
@ -74,6 +75,7 @@ namespace {
class Reassociate : public FunctionPass {
DenseMap<BasicBlock*, unsigned> RankMap;
DenseMap<AssertingVH<>, unsigned> ValueRankMap;
SmallVector<WeakVH, 8> DeadInsts;
bool MadeChange;
public:
static char ID; // Pass identification, replacement for typeid
@ -113,13 +115,13 @@ FunctionPass *llvm::createReassociatePass() { return new Reassociate(); }
void Reassociate::RemoveDeadBinaryOp(Value *V) {
Instruction *Op = dyn_cast<Instruction>(V);
if (!Op || !isa<BinaryOperator>(Op) || !Op->use_empty())
if (!Op || !isa<BinaryOperator>(Op))
return;
Value *LHS = Op->getOperand(0), *RHS = Op->getOperand(1);
ValueRankMap.erase(Op);
Op->eraseFromParent();
DeadInsts.push_back(Op);
RemoveDeadBinaryOp(LHS);
RemoveDeadBinaryOp(RHS);
}
@ -603,7 +605,7 @@ Value *Reassociate::RemoveFactorFromExpression(Value *V, Value *Factor) {
// remaining operand.
if (Factors.size() == 1) {
ValueRankMap.erase(BO);
BO->eraseFromParent();
DeadInsts.push_back(BO);
V = Factors[0].Op;
} else {
RewriteExprTree(BO, Factors);
@ -1093,6 +1095,12 @@ bool Reassociate::runOnFunction(Function &F) {
for (Function::iterator FI = F.begin(), FE = F.end(); FI != FE; ++FI)
ReassociateBB(FI);
// Now that we're done, delete any instructions which are no longer used.
while (!DeadInsts.empty())
if (Instruction *Inst =
cast_or_null<Instruction>((Value *)DeadInsts.pop_back_val()))
RecursivelyDeleteTriviallyDeadInstructions(Inst);
// We are done with the rank map.
RankMap.clear();
ValueRankMap.clear();

25
test/Transforms/Reassociate/crash.ll
View File

@ -42,3 +42,28 @@ define i32 @test3(i32 %Arg, i32 %x1, i32 %x2, i32 %x3) {
%E = add i32 %D, %C
ret i32 %E
}
; rdar://9096268
define void @x66303361ae3f602889d1b7d0f86e5455(i8* %arg) nounwind {
_:
br label %_33
_33: ; preds = %_33, %_
%tmp348 = load i8* %arg, align 1
%tmp349 = lshr i8 %tmp348, 7
%tmp350 = or i8 %tmp349, 42
%tmp351 = add i8 %tmp350, -42
%tmp352 = zext i8 %tmp351 to i32
%tmp358 = add i32 %tmp352, -501049439
%tmp359 = mul i32 %tmp358, %tmp358
%tmp360 = mul i32 %tmp352, %tmp352
%tmp361 = sub i32 %tmp359, %tmp360
%tmp362 = mul i32 %tmp361, -920056735
%tmp363 = add i32 %tmp362, 501049439
%tmp364 = add i32 %tmp362, -2000262972
%tmp365 = sub i32 %tmp363, %tmp364
%tmp366 = sub i32 -501049439, %tmp362
%tmp367 = add i32 %tmp365, %tmp366
br label %_33
}