[llvm] r332682 - [X86DomainReassignment] Don't compare stack-allocated values by address
Keno Fischer via llvm-commits
llvm-commits at lists.llvm.org
Thu May 17 18:03:01 PDT 2018
Author: kfischer
Date: Thu May 17 18:03:01 2018
New Revision: 332682
URL: http://llvm.org/viewvc/llvm-project?rev=332682&view=rev
Log:
[X86DomainReassignment] Don't compare stack-allocated values by address
Summary:
The Closure allocated in the main loop is allocated on the stack. However,
later in the code its address is taken (and used for comparisons). This
obviously doesn't work. In fact, the Closure will get the same stack address
during every loop iteration, rendering the check that intended to identify
Closure conflicts entirely ineffective. Fix this bug by giving every Closure
a unique ID and using that for comparison. Alternatively, we could heap
allocate the closure object.
Fixes PR37396
Fixes JuliaLang/julia#27032
Reviewers: craig.topper, guyblank
Reviewed By: craig.topper
Subscribers: vchuravy, llvm-commits
Differential Revision: https://reviews.llvm.org/D46800
Added:
llvm/trunk/test/CodeGen/X86/domain-reassignment-test.ll
Modified:
llvm/trunk/lib/Target/X86/X86DomainReassignment.cpp
Modified: llvm/trunk/lib/Target/X86/X86DomainReassignment.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86DomainReassignment.cpp?rev=332682&r1=332681&r2=332682&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86DomainReassignment.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86DomainReassignment.cpp Thu May 17 18:03:01 2018
@@ -26,6 +26,7 @@
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/TargetRegisterInfo.h"
#include "llvm/Support/Debug.h"
+#include "llvm/Support/Printable.h"
#include <bitset>
using namespace llvm;
@@ -291,8 +292,12 @@ private:
/// Domains which this closure can legally be reassigned to.
std::bitset<NumDomains> LegalDstDomains;
+ /// An ID to uniquely identify this closure, even when it gets
+ /// moved around
+ unsigned ID;
+
public:
- Closure(std::initializer_list<RegDomain> LegalDstDomainList) {
+ Closure(unsigned ID, std::initializer_list<RegDomain> LegalDstDomainList) : ID(ID) {
for (RegDomain D : LegalDstDomainList)
LegalDstDomains.set(D);
}
@@ -328,6 +333,27 @@ public:
return Instrs;
}
+ LLVM_DUMP_METHOD void dump(const MachineRegisterInfo *MRI) const {
+ dbgs() << "Registers: ";
+ bool First = true;
+ for (unsigned Reg : Edges) {
+ if (!First)
+ dbgs() << ", ";
+ First = false;
+ dbgs() << printReg(Reg, MRI->getTargetRegisterInfo(), 0, MRI);
+ }
+ dbgs() << "\n" << "Instructions:";
+ for (MachineInstr *MI : Instrs) {
+ dbgs() << "\n ";
+ MI->print(dbgs());
+ }
+ dbgs() << "\n";
+ }
+
+ unsigned getID() const {
+ return ID;
+ }
+
};
class X86DomainReassignment : public MachineFunctionPass {
@@ -339,7 +365,7 @@ class X86DomainReassignment : public Mac
DenseSet<unsigned> EnclosedEdges;
/// All instructions that are included in some closure.
- DenseMap<MachineInstr *, Closure *> EnclosedInstrs;
+ DenseMap<MachineInstr *, unsigned> EnclosedInstrs;
public:
static char ID;
@@ -416,14 +442,14 @@ void X86DomainReassignment::visitRegiste
void X86DomainReassignment::encloseInstr(Closure &C, MachineInstr *MI) {
auto I = EnclosedInstrs.find(MI);
if (I != EnclosedInstrs.end()) {
- if (I->second != &C)
+ if (I->second != C.getID())
// Instruction already belongs to another closure, avoid conflicts between
// closure and mark this closure as illegal.
C.setAllIllegal();
return;
}
- EnclosedInstrs[MI] = &C;
+ EnclosedInstrs[MI] = C.getID();
C.addInstruction(MI);
// Mark closure as illegal for reassignment to domains, if there is no
@@ -705,6 +731,7 @@ bool X86DomainReassignment::runOnMachine
std::vector<Closure> Closures;
// Go over all virtual registers and calculate a closure.
+ unsigned ClosureID = 0;
for (unsigned Idx = 0; Idx < MRI->getNumVirtRegs(); ++Idx) {
unsigned Reg = TargetRegisterInfo::index2VirtReg(Idx);
@@ -717,7 +744,7 @@ bool X86DomainReassignment::runOnMachine
continue;
// Calculate closure starting with Reg.
- Closure C({MaskDomain});
+ Closure C(ClosureID++, {MaskDomain});
buildClosure(C, Reg);
// Collect all closures that can potentially be converted.
@@ -725,12 +752,14 @@ bool X86DomainReassignment::runOnMachine
Closures.push_back(std::move(C));
}
- for (Closure &C : Closures)
+ for (Closure &C : Closures) {
+ DEBUG(C.dump(MRI));
if (isReassignmentProfitable(C, MaskDomain)) {
reassign(C, MaskDomain);
++NumClosuresConverted;
Changed = true;
}
+ }
DeleteContainerSeconds(Converters);
Added: llvm/trunk/test/CodeGen/X86/domain-reassignment-test.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/domain-reassignment-test.ll?rev=332682&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/X86/domain-reassignment-test.ll (added)
+++ llvm/trunk/test/CodeGen/X86/domain-reassignment-test.ll Thu May 17 18:03:01 2018
@@ -0,0 +1,37 @@
+; RUN: llc -mcpu=skylake-avx512 -mtriple=x86_64-unknown-linux-gnu %s -o - | FileCheck %s
+; RUN: llc -mcpu=skylake-avx512 -mtriple=x86_64-unknown-linux-gnu %s -o - | llvm-mc
+
+; Check that the X86 domain reassignment pass doesn't introduce an illegal
+; test instruction. See PR37396
+define void @japi1_foo2_34617() {
+pass2:
+ br label %if5
+
+L174:
+ %tmp = icmp sgt <2 x i64> undef, zeroinitializer
+ %tmp1 = icmp sle <2 x i64> undef, undef
+ %tmp2 = and <2 x i1> %tmp, %tmp1
+ %tmp3 = extractelement <2 x i1> %tmp2, i32 0
+ %tmp4 = extractelement <2 x i1> %tmp2, i32 1
+ %tmp106 = and i1 %tmp4, %tmp3
+ %tmp107 = zext i1 %tmp106 to i8
+ %tmp108 = and i8 %tmp122, %tmp107
+ %tmp109 = icmp eq i8 %tmp108, 0
+; CHECK-NOT: testb {{%k[0-7]}}
+ br i1 %tmp109, label %L188, label %L190
+
+if5:
+ %b.055 = phi i8 [ 1, %pass2 ], [ %tmp122, %if5 ]
+ %tmp118 = icmp sgt i64 undef, 0
+ %tmp119 = icmp sle i64 undef, undef
+ %tmp120 = and i1 %tmp118, %tmp119
+ %tmp121 = zext i1 %tmp120 to i8
+ %tmp122 = and i8 %b.055, %tmp121
+ br i1 undef, label %L174, label %if5
+
+L188:
+ unreachable
+
+L190:
+ ret void
+}
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