llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT-->
@llvm/pr-subscribers-clang
Author: None (eddyz87)
<details>
<summary>Changes</summary>
This commit aims to support BPF arena kernel side feature [0]:
- arena is a memory region accessible from both BPF program and userspace;
- base pointers for this memory region differ between kernel and user spaces;
- `dst_reg = cast_kern(src_reg, addr_space_no)` translates src_reg, user space
pointer within arena, to dst_reg, equivalent kernel space pointer within arena
(both pointers have identical offset from arena start), addr_space_no is an
immediate constant, used to identify the particular arena;
- `dst_reg = cast_user(src_reg, addr_space_no)` is similar but in opposite
direction: converts kernel space arena pointer to user space arena pointer.
On the LLVM side, the goal is to make load and store operations on arena
pointers "transparent" for BPF programs:
- assume that pointers with non-zero address space are pointers to
arena memory;
- assume that arena is identified by address space number;
- assume that address space zero corresponds to kernel address space;
- assume that every BPF-side load or store from arena is done via pointer in
user address space, thus convert base pointers using `cast_kern`;
Only load, store, cmpxchg and atomicrmw IR instructions are handled by this
transformation.
For example, the following C code:
```c
void copy(int __as *from, int __as *to) { *to = *from; }
```
Compiled to the following IR:
```llvm
define void @<!-- -->copy(ptr addrspace(1) %from, ptr addrspace(1) %to) {
entry:
%0 = load i32, ptr addrspace(1) %from, align 4
store i32 %0, ptr addrspace(1) %to, align 4
ret void
}
```
Is transformed to:
```llvm
%to2 = addrspacecast ptr addrspace(1) %to to ptr ;; !
%from1 = addrspacecast ptr addrspace(1) %from to ptr ;; !
%0 = load i32, ptr %from1, align 4, !tbaa !3
store i32 %0, ptr %to2, align 4, !tbaa !3
ret void
```
And compiled as:
```asm
r2 = cast_kern(r2, 1)
r1 = cast_kern(r1, 1)
r1 = *(u32 *)(r1 + 0)
*(u32 *)(r2 + 0) = r1
exit
```
---
Patch is 33.97 KiB, truncated to 20.00 KiB below, full version:
https://github.com/llvm/llvm-project/pull/79902.diff
21 Files Affected:
- (modified) clang/lib/Basic/Targets/BPF.cpp (+3)
- (modified) clang/test/Preprocessor/bpf-predefined-macros.c (+8)
- (modified) llvm/lib/Target/BPF/BPF.h (+8)
- (added) llvm/lib/Target/BPF/BPFASpaceCastSimplifyPass.cpp (+92)
- (modified) llvm/lib/Target/BPF/BPFCheckAndAdjustIR.cpp (+116)
- (modified) llvm/lib/Target/BPF/BPFISelLowering.cpp (+46)
- (modified) llvm/lib/Target/BPF/BPFISelLowering.h (+3-1)
- (modified) llvm/lib/Target/BPF/BPFInstrInfo.td (+25)
- (modified) llvm/lib/Target/BPF/BPFTargetMachine.cpp (+5)
- (modified) llvm/lib/Target/BPF/CMakeLists.txt (+1)
- (added) llvm/test/CodeGen/BPF/addr-space-auto-casts.ll (+78)
- (added) llvm/test/CodeGen/BPF/addr-space-cast.ll (+22)
- (added) llvm/test/CodeGen/BPF/addr-space-gep-chain.ll (+25)
- (added) llvm/test/CodeGen/BPF/addr-space-globals.ll (+30)
- (added) llvm/test/CodeGen/BPF/addr-space-globals2.ll (+25)
- (added) llvm/test/CodeGen/BPF/addr-space-phi.ll (+52)
- (added) llvm/test/CodeGen/BPF/addr-space-simplify-1.ll (+19)
- (added) llvm/test/CodeGen/BPF/addr-space-simplify-2.ll (+21)
- (added) llvm/test/CodeGen/BPF/addr-space-simplify-3.ll (+26)
- (added) llvm/test/CodeGen/BPF/addr-space-simplify-4.ll (+21)
- (added) llvm/test/CodeGen/BPF/addr-space-simplify-5.ll (+25)
``````````diff
diff --git a/clang/lib/Basic/Targets/BPF.cpp b/clang/lib/Basic/Targets/BPF.cpp
index e3fbbb720d0694..26a54f631fcfc4 100644
--- a/clang/lib/Basic/Targets/BPF.cpp
+++ b/clang/lib/Basic/Targets/BPF.cpp
@@ -35,6 +35,9 @@ void BPFTargetInfo::getTargetDefines(const LangOptions &Opts,
Builder.defineMacro("__BPF_CPU_VERSION__", "0");
return;
}
+
+ Builder.defineMacro("__BPF_FEATURE_ARENA_CAST");
+
if (CPU.empty() || CPU == "generic" || CPU == "v1") {
Builder.defineMacro("__BPF_CPU_VERSION__", "1");
return;
diff --git a/clang/test/Preprocessor/bpf-predefined-macros.c
b/clang/test/Preprocessor/bpf-predefined-macros.c
index ff4d00ac3bcfcc..fea24d1ea0ff7b 100644
--- a/clang/test/Preprocessor/bpf-predefined-macros.c
+++ b/clang/test/Preprocessor/bpf-predefined-macros.c
@@ -61,6 +61,9 @@ int r;
#ifdef __BPF_FEATURE_ST
int s;
#endif
+#ifdef __BPF_FEATURE_ARENA_CAST
+int t;
+#endif
// CHECK: int b;
// CHECK: int c;
@@ -90,6 +93,11 @@ int s;
// CPU_V4: int r;
// CPU_V4: int s;
+// CPU_V1: int t;
+// CPU_V2: int t;
+// CPU_V3: int t;
+// CPU_V4: int t;
+
// CPU_GENERIC: int g;
// CPU_PROBE: int f;
diff --git a/llvm/lib/Target/BPF/BPF.h b/llvm/lib/Target/BPF/BPF.h
index 5c77d183e1ef3d..bbdbdbbde53228 100644
--- a/llvm/lib/Target/BPF/BPF.h
+++ b/llvm/lib/Target/BPF/BPF.h
@@ -66,6 +66,14 @@ class BPFIRPeepholePass : public
PassInfoMixin<BPFIRPeepholePass> {
static bool isRequired() { return true; }
};
+class BPFASpaceCastSimplifyPass
+ : public PassInfoMixin<BPFASpaceCastSimplifyPass> {
+public:
+ PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM);
+
+ static bool isRequired() { return true; }
+};
+
class BPFAdjustOptPass : public PassInfoMixin<BPFAdjustOptPass> {
public:
PreservedAnalyses run(Module &M, ModuleAnalysisManager &AM);
diff --git a/llvm/lib/Target/BPF/BPFASpaceCastSimplifyPass.cpp
b/llvm/lib/Target/BPF/BPFASpaceCastSimplifyPass.cpp
new file mode 100644
index 00000000000000..d32cecc073fab9
--- /dev/null
+++ b/llvm/lib/Target/BPF/BPFASpaceCastSimplifyPass.cpp
@@ -0,0 +1,92 @@
+//===------------ BPFIRPeephole.cpp - IR Peephole Transformation
----------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM
Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "BPF.h"
+#include <optional>
+
+#define DEBUG_TYPE "bpf-aspace-simplify"
+
+using namespace llvm;
+
+namespace {
+
+struct CastGEPCast {
+ AddrSpaceCastInst *OuterCast;
+
+ // Match chain of instructions:
+ // %inner = addrspacecast N->M
+ // %gep = getelementptr %inner, ...
+ // %outer = addrspacecast M->N %gep
+ // Where I is %outer.
+ static std::optional<CastGEPCast> match(Value *I) {
+ auto *OuterCast = dyn_cast<AddrSpaceCastInst>(I);
+ if (!OuterCast)
+ return std::nullopt;
+ auto *GEP = dyn_cast<GetElementPtrInst>(OuterCast->getPointerOperand());
+ if (!GEP)
+ return std::nullopt;
+ auto *InnerCast = dyn_cast<AddrSpaceCastInst>(GEP->getPointerOperand());
+ if (!InnerCast)
+ return std::nullopt;
+ if (InnerCast->getSrcAddressSpace() != OuterCast->getDestAddressSpace())
+ return std::nullopt;
+ if (InnerCast->getDestAddressSpace() != OuterCast->getSrcAddressSpace())
+ return std::nullopt;
+ return CastGEPCast{OuterCast};
+ }
+
+ static PointerType *changeAddressSpace(PointerType *Ty, unsigned AS) {
+ return Ty->get(Ty->getContext(), AS);
+ }
+
+ // Assuming match(this->OuterCast) is true, convert:
+ // (addrspacecast M->N (getelementptr (addrspacecast N->M ptr) ...))
+ // To:
+ // (getelementptr ptr ...)
+ GetElementPtrInst *rewrite() {
+ auto *GEP = cast<GetElementPtrInst>(OuterCast->getPointerOperand());
+ auto *InnerCast = cast<AddrSpaceCastInst>(GEP->getPointerOperand());
+ unsigned AS = OuterCast->getDestAddressSpace();
+ auto *NewGEP = cast<GetElementPtrInst>(GEP->clone());
+ NewGEP->setName(GEP->getName());
+ NewGEP->insertAfter(OuterCast);
+ NewGEP->setOperand(0, InnerCast->getPointerOperand());
+ auto *GEPTy = cast<PointerType>(GEP->getType());
+ NewGEP->mutateType(changeAddressSpace(GEPTy, AS));
+ OuterCast->replaceAllUsesWith(NewGEP);
+ OuterCast->eraseFromParent();
+ if (GEP->use_empty())
+ GEP->eraseFromParent();
+ if (InnerCast->use_empty())
+ InnerCast->eraseFromParent();
+ return NewGEP;
+ }
+};
+
+} // anonymous namespace
+
+PreservedAnalyses BPFASpaceCastSimplifyPass::run(Function &F,
+ FunctionAnalysisManager &AM) {
+ SmallVector<CastGEPCast, 16> WorkList;
+ bool Changed = false;
+ for (BasicBlock &BB : F) {
+ for (Instruction &I : BB)
+ if (auto It = CastGEPCast::match(&I))
+ WorkList.push_back(It.value());
+ Changed |= !WorkList.empty();
+
+ while (!WorkList.empty()) {
+ CastGEPCast InsnChain = WorkList.pop_back_val();
+ GetElementPtrInst *NewGEP = InsnChain.rewrite();
+ for (User *U : NewGEP->users())
+ if (auto It = CastGEPCast::match(U))
+ WorkList.push_back(It.value());
+ }
+ }
+ return Changed ? PreservedAnalyses::none() : PreservedAnalyses::all();
+}
diff --git a/llvm/lib/Target/BPF/BPFCheckAndAdjustIR.cpp
b/llvm/lib/Target/BPF/BPFCheckAndAdjustIR.cpp
index 81effc9b1db46c..edd59aaa6d01d2 100644
--- a/llvm/lib/Target/BPF/BPFCheckAndAdjustIR.cpp
+++ b/llvm/lib/Target/BPF/BPFCheckAndAdjustIR.cpp
@@ -14,6 +14,8 @@
// optimizations are done and those builtins can be removed.
// - remove llvm.bpf.getelementptr.and.load builtins.
// - remove llvm.bpf.getelementptr.and.store builtins.
+// - for loads and stores with base addresses from non-zero address space
+// cast base address to zero address space (support for BPF arenas).
//
//===----------------------------------------------------------------------===//
@@ -55,6 +57,7 @@ class BPFCheckAndAdjustIR final : public ModulePass {
bool removeCompareBuiltin(Module &M);
bool sinkMinMax(Module &M);
bool removeGEPBuiltins(Module &M);
+ bool insertASpaceCasts(Module &M);
};
} // End anonymous namespace
@@ -416,11 +419,124 @@ bool BPFCheckAndAdjustIR::removeGEPBuiltins(Module &M) {
return Changed;
}
+// Wrap ToWrap with cast to address space zero:
+// - if ToWrap is a getelementptr,
+// wrap it's base pointer instead and return a copy;
+// - if ToWrap is Instruction, insert address space cast
+// immediately after ToWrap;
+// - if ToWrap is not an Instruction (function parameter
+// or a global value), insert address space cast at the
+// beginning of the Function F;
+// - use Cache to avoid inserting too many casts;
+static Value *aspaceWrapValue(DenseMap<Value *, Value *> &Cache, Function *F,
+ Value *ToWrap) {
+ auto It = Cache.find(ToWrap);
+ if (It != Cache.end())
+ return It->getSecond();
+
+ if (auto *GEP = dyn_cast<GetElementPtrInst>(ToWrap)) {
+ Value *Ptr = GEP->getPointerOperand();
+ Value *WrappedPtr = aspaceWrapValue(Cache, F, Ptr);
+ auto *GEPTy = cast<PointerType>(GEP->getType());
+ auto *NewGEP = GEP->clone();
+ NewGEP->insertAfter(GEP);
+ NewGEP->mutateType(GEPTy->getPointerTo(0));
+ NewGEP->setOperand(GEP->getPointerOperandIndex(), WrappedPtr);
+ NewGEP->setName(GEP->getName());
+ Cache[ToWrap] = NewGEP;
+ return NewGEP;
+ }
+
+ IRBuilder IB(F->getContext());
+ if (Instruction *InsnPtr = dyn_cast<Instruction>(ToWrap))
+ IB.SetInsertPoint(*InsnPtr->getInsertionPointAfterDef());
+ else
+ IB.SetInsertPoint(F->getEntryBlock().getFirstInsertionPt());
+ auto *PtrTy = cast<PointerType>(ToWrap->getType());
+ auto *ASZeroPtrTy = PtrTy->getPointerTo(0);
+ auto *ACast = IB.CreateAddrSpaceCast(ToWrap, ASZeroPtrTy, ToWrap->getName());
+ Cache[ToWrap] = ACast;
+ return ACast;
+}
+
+// Wrap a pointer operand OpNum of instruction I
+// with cast to address space zero
+static void aspaceWrapOperand(DenseMap<Value *, Value *> &Cache, Instruction
*I,
+ unsigned OpNum) {
+ Value *OldOp = I->getOperand(OpNum);
+ if (OldOp->getType()->getPointerAddressSpace() == 0)
+ return;
+
+ Value *NewOp = aspaceWrapValue(Cache, I->getFunction(), OldOp);
+ I->setOperand(OpNum, NewOp);
+ // Check if there are any remaining users of old GEP,
+ // delete those w/o users
+ for (;;) {
+ auto *OldGEP = dyn_cast<GetElementPtrInst>(OldOp);
+ if (!OldGEP)
+ break;
+ if (!OldGEP->use_empty())
+ break;
+ OldOp = OldGEP->getPointerOperand();
+ OldGEP->eraseFromParent();
+ }
+}
+
+// Support for BPF arenas:
+// - for each function in the module M, update pointer operand of
+// each memory access instruction (load/store/cmpxchg/atomicrmw)
+// by casting it from non-zero address space to zero address space, e.g:
+//
+// (load (ptr addrspace (N) %p) ...)
+// -> (load (addrspacecast ptr addrspace (N) %p to ptr))
+//
+// - assign section with name .arena.N for globals defined in
+// non-zero address space N
+bool BPFCheckAndAdjustIR::insertASpaceCasts(Module &M) {
+ bool Changed = false;
+ for (Function &F : M) {
+ DenseMap<Value *, Value *> CastsCache;
+ for (BasicBlock &BB : F) {
+ for (Instruction &I : BB) {
+ unsigned PtrOpNum;
+
+ if (auto *LD = dyn_cast<LoadInst>(&I))
+ PtrOpNum = LD->getPointerOperandIndex();
+ else if (auto *ST = dyn_cast<StoreInst>(&I))
+ PtrOpNum = ST->getPointerOperandIndex();
+ else if (auto *CmpXchg = dyn_cast<AtomicCmpXchgInst>(&I))
+ PtrOpNum = CmpXchg->getPointerOperandIndex();
+ else if (auto *RMW = dyn_cast<AtomicRMWInst>(&I))
+ PtrOpNum = RMW->getPointerOperandIndex();
+ else
+ continue;
+
+ aspaceWrapOperand(CastsCache, &I, PtrOpNum);
+ }
+ }
+ Changed |= !CastsCache.empty();
+ }
+ // Merge all globals within same address space into single
+ // .arena.<addr space no> section
+ for (GlobalVariable &G : M.globals()) {
+ if (G.getAddressSpace() == 0 || G.hasSection())
+ continue;
+ SmallString<16> SecName;
+ raw_svector_ostream OS(SecName);
+ OS << ".arena." << G.getAddressSpace();
+ G.setSection(SecName);
+ // Prevent having separate section for constants
+ G.setConstant(false);
+ }
+ return Changed;
+}
+
bool BPFCheckAndAdjustIR::adjustIR(Module &M) {
bool Changed = removePassThroughBuiltin(M);
Changed = removeCompareBuiltin(M) || Changed;
Changed = sinkMinMax(M) || Changed;
Changed = removeGEPBuiltins(M) || Changed;
+ Changed = insertASpaceCasts(M) || Changed;
return Changed;
}
diff --git a/llvm/lib/Target/BPF/BPFISelLowering.cpp
b/llvm/lib/Target/BPF/BPFISelLowering.cpp
index 4d8ace7c1ece02..0b6d4eccba1b86 100644
--- a/llvm/lib/Target/BPF/BPFISelLowering.cpp
+++ b/llvm/lib/Target/BPF/BPFISelLowering.cpp
@@ -24,6 +24,7 @@
#include "llvm/CodeGen/ValueTypes.h"
#include "llvm/IR/DiagnosticInfo.h"
#include "llvm/IR/DiagnosticPrinter.h"
+#include "llvm/IR/IntrinsicsBPF.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/MathExtras.h"
@@ -75,6 +76,8 @@ BPFTargetLowering::BPFTargetLowering(const TargetMachine &TM,
setOperationAction(ISD::STACKSAVE, MVT::Other, Expand);
setOperationAction(ISD::STACKRESTORE, MVT::Other, Expand);
+ setOperationAction(ISD::ADDRSPACECAST, MVT::i64, Custom);
+
// Set unsupported atomic operations as Custom so
// we can emit better error messages than fatal error
// from selectiondag.
@@ -315,6 +318,8 @@ SDValue BPFTargetLowering::LowerOperation(SDValue Op,
SelectionDAG &DAG) const {
return LowerSDIVSREM(Op, DAG);
case ISD::DYNAMIC_STACKALLOC:
return LowerDYNAMIC_STACKALLOC(Op, DAG);
+ case ISD::ADDRSPACECAST:
+ return LowerADDRSPACECAST(Op, DAG);
}
}
@@ -638,6 +643,45 @@ SDValue BPFTargetLowering::LowerDYNAMIC_STACKALLOC(SDValue
Op,
return DAG.getMergeValues(Ops, SDLoc());
}
+enum {
+ CAST_TO_KERNEL = 1,
+ CAST_TO_USER = 2,
+};
+
+SDValue BPFTargetLowering::LowerADDRSPACECAST(SDValue Op,
+ SelectionDAG &DAG) const {
+ auto *ACast = dyn_cast<AddrSpaceCastSDNode>(Op);
+ const SDValue &Ptr = ACast->getOperand(0);
+ unsigned SrcAS = ACast->getSrcAddressSpace();
+ unsigned DstAS = ACast->getDestAddressSpace();
+ SDLoc DL(Op);
+
+ if (SrcAS > 0 && DstAS > 0) {
+ SmallString<64> Msg;
+ raw_svector_ostream OS(Msg);
+ OS << "Can't cast address space " << SrcAS << " to " << DstAS
+ << ": either source or destination address space has to be zero";
+ fail(DL, DAG, Msg);
+ return Op.getOperand(0);
+ }
+
+ if (SrcAS == 0 && DstAS == 0)
+ return Op.getOperand(0);
+
+ unsigned Code;
+ unsigned ASpace;
+ if (SrcAS > 0) {
+ Code = CAST_TO_KERNEL;
+ ASpace = SrcAS;
+ } else {
+ Code = CAST_TO_USER;
+ ASpace = DstAS;
+ }
+ return DAG.getNode(BPFISD::ADDR_SPACE_CAST, DL, Op.getValueType(), Ptr,
+ DAG.getTargetConstant(Code, DL, MVT::i64),
+ DAG.getTargetConstant(ASpace, DL, MVT::i64));
+}
+
SDValue BPFTargetLowering::LowerBR_CC(SDValue Op, SelectionDAG &DAG) const {
SDValue Chain = Op.getOperand(0);
ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(1))->get();
@@ -687,6 +731,8 @@ const char *BPFTargetLowering::getTargetNodeName(unsigned
Opcode) const {
return "BPFISD::Wrapper";
case BPFISD::MEMCPY:
return "BPFISD::MEMCPY";
+ case BPFISD::ADDR_SPACE_CAST:
+ return "BPFISD::ADDR_SPACE_CAST";
}
return nullptr;
}
diff --git a/llvm/lib/Target/BPF/BPFISelLowering.h
b/llvm/lib/Target/BPF/BPFISelLowering.h
index 819711b650c15f..437f0e89af56b8 100644
--- a/llvm/lib/Target/BPF/BPFISelLowering.h
+++ b/llvm/lib/Target/BPF/BPFISelLowering.h
@@ -28,7 +28,8 @@ enum NodeType : unsigned {
SELECT_CC,
BR_CC,
Wrapper,
- MEMCPY
+ MEMCPY,
+ ADDR_SPACE_CAST,
};
}
@@ -75,6 +76,7 @@ class BPFTargetLowering : public TargetLowering {
SDValue LowerSDIVSREM(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerDYNAMIC_STACKALLOC(SDValue Op, SelectionDAG &DAG) const;
+ SDValue LowerADDRSPACECAST(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerBR_CC(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerGlobalAddress(SDValue Op, SelectionDAG &DAG) const;
diff --git a/llvm/lib/Target/BPF/BPFInstrInfo.td
b/llvm/lib/Target/BPF/BPFInstrInfo.td
index 7d443a34490146..62e285dbc4c31e 100644
--- a/llvm/lib/Target/BPF/BPFInstrInfo.td
+++ b/llvm/lib/Target/BPF/BPFInstrInfo.td
@@ -31,6 +31,9 @@ def SDT_BPFMEMCPY : SDTypeProfile<0, 4, [SDTCisVT<0,
i64>,
SDTCisVT<1, i64>,
SDTCisVT<2, i64>,
SDTCisVT<3, i64>]>;
+def SDT_BPFAddrSpaceCast : SDTypeProfile<0, 3, [SDTCisPtrTy<0>,
+ SDTCisVT<1, i64>,
+ SDTCisVT<2, i64>]>;
def BPFcall : SDNode<"BPFISD::CALL", SDT_BPFCall,
[SDNPHasChain, SDNPOptInGlue, SDNPOutGlue,
@@ -49,6 +52,7 @@ def BPFWrapper : SDNode<"BPFISD::Wrapper",
SDT_BPFWrapper>;
def BPFmemcpy : SDNode<"BPFISD::MEMCPY", SDT_BPFMEMCPY,
[SDNPHasChain, SDNPInGlue, SDNPOutGlue,
SDNPMayStore, SDNPMayLoad]>;
+def BPFAddrSpaceCast : SDNode<"BPFISD::ADDR_SPACE_CAST",
SDT_BPFAddrSpaceCast>;
def BPFIsLittleEndian : Predicate<"Subtarget->isLittleEndian()">;
def BPFIsBigEndian : Predicate<"!Subtarget->isLittleEndian()">;
def BPFHasALU32 : Predicate<"Subtarget->getHasAlu32()">;
@@ -420,6 +424,27 @@ let Predicates = [BPFHasMovsx] in {
}
}
+def CAST_DIR {
+ int TO_KERN = 1;
+ int TO_USER = 2;
+}
+
+class ADDR_SPACE_CAST<int Code, string AsmPattern>
+ : ALU_RR<BPF_ALU64, BPF_MOV, 64,
+ (outs GPR:$dst),
+ (ins GPR:$src, i64imm:$imm),
+ AsmPattern,
+ []> {
+ bits<64> imm;
+ let Inst{47-32} = Code;
+ let Inst{31-0} = imm{31-0};
+}
+def CAST_KERN : ADDR_SPACE_CAST<CAST_DIR.TO_KERN, "$dst = cast_kern($src,
$imm)">;
+def CAST_USER : ADDR_SPACE_CAST<CAST_DIR.TO_USER, "$dst = cast_user($src,
$imm)">;
+
+def : Pat<(BPFAddrSpaceCast GPR:$src, CAST_DIR.TO_KERN, i64:$as), (CAST_KERN
$src, $as)>;
+def : Pat<(BPFAddrSpaceCast GPR:$src, CAST_DIR.TO_USER, i64:$as), (CAST_USER
$src, $as)>;
+
def FI_ri
: TYPE_LD_ST<BPF_IMM.Value, BPF_DW.Value,
(outs GPR:$dst),
diff --git a/llvm/lib/Target/BPF/BPFTargetMachine.cpp
b/llvm/lib/Target/BPF/BPFTargetMachine.cpp
index 8a6e7ae3663e0d..2e956e6c25b1b1 100644
--- a/llvm/lib/Target/BPF/BPFTargetMachine.cpp
+++ b/llvm/lib/Target/BPF/BPFTargetMachine.cpp
@@ -121,6 +121,10 @@ void BPFTargetMachine::registerPassBuilderCallbacks(
FPM.addPass(BPFPreserveStaticOffsetPass(false));
return true;
}
+ if (PassName == "bpf-aspace-simplify") {
+ FPM.addPass(BPFASpaceCastSimplifyPass());
+ return true;
+ }
return false;
});
PB.registerPipelineStartEPCallback(
@@ -135,6 +139,7 @@ void BPFTargetMachine::registerPassBuilderCallbacks(
PB.registerPeepholeEPCallback([=](FunctionPassManager &FPM,
OptimizationLevel Level) {
FPM.addPass(SimplifyCFGPass(SimplifyCFGOptions().hoistCommonInsts(true)));
+ FPM.addPass(BPFASpaceCastSimplifyPass());
});
PB.registerScalarOptimizerLateEPCallback(
[=](FunctionPassManager &FPM, OptimizationLevel Level) {
diff --git a/llvm/lib/Target/BPF/CMakeLists.txt
b/llvm/lib/Target/BPF/CMakeLists.txt
index d88e7ade40b9a0..cb21ed03a86c1e 100644
--- a/llvm/lib/Target/BPF/CMakeLists.txt
+++ b/llvm/lib/Target/BPF/CMakeLists.txt
@@ -24,6 +24,7 @@ add_llvm_target(BPFCodeGen
BPFAbstractMemberAccess.cpp
BPFAdjustOpt.cpp
BPFAsmPrinter.cpp
+ BPFASpaceCastSimplifyPass.cpp
BPFCheckAndAdjustIR.cpp
BPFFrameLowering.cpp
BPFInstrInfo.cpp
diff --git a/llvm/test/CodeGen/BPF/addr-space-auto-casts.ll
b/llvm/test/CodeGen/BPF/addr-space-auto-casts.ll
new file mode 100644
index 00000000000000..08e11e861c71cb
--- /dev/null
+++ b/llvm/test/CodeGen/BPF/addr-space-auto-casts.ll
@@ -0,0 +1,78 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
UTC_ARGS: --version 4
+; RUN: opt --bpf-check-and-opt-ir -S -mtriple=bpf-pc-linux < %s | FileCheck %s
+
+define void @simple_store(ptr addrspace(272) %foo) {
+; CHECK-LABEL: define void @simple_store(
+; CHECK-SAME: ptr addrspace(272) [[FOO:%.*]]) {
+; CHECK-NEXT: entry:
+; CHECK-NEXT: [[FOO1:%.*]] = addrspacecast ptr addrspace(272) [[FOO]] to ptr
+; CHECK-NEXT: [[ADD_PTR2:%.*]] = getelementptr inbounds i8, ptr [[FOO1]],
i64 16
+; CHECK-NEXT: store volatile i32 57005, ptr [[ADD_PTR2]], align 4
+; CHECK-NEXT: [[ADD_PTR13:%.*]] = getelementptr inbounds i8, ptr [[FOO1]],
i64 12
+; CHECK-NEXT: store volatile i32 48879, ptr [[ADD_PTR13]], align 4
+; CHECK-NEXT: ret void
+;
+entry:
+ %add.ptr = getelementptr inbounds i8, ptr addrspace(272) %foo, i64 16
+ store volatile i32 57005, ptr addrspace(272) %add.ptr, align 4
+ %add.ptr1 = getelementptr inbounds i8, ptr addrspace(272) %foo, i64 12
+ store volatile i32 48879, ptr addrspace(272) %add.ptr1, align 4
+ ret void
+}
+
+define void @separate_addr_store(ptr addrspace(272) %foo, ptr addrspace(272)
%bar) {
+; CHECK-LABEL: define void @separate_addr_store(
+; CHECK-SAME: ptr addrspace(272) [[FOO:%.*]], ptr addrspace(272) [[BAR:%.*]]) {
+; CHECK-NEXT: entry:
+; CHECK-NEXT: [[BAR3:%.*]] = addrspacecast ptr addrspace(272) [[BAR]] to ptr
+; CHECK-NEXT: [[FOO1:%.*]] = addrspacecast ptr addrspace(272) [[FOO]] to ptr
+; CHECK-NEXT: [[ADD_PTR2:%.*]] = getelementptr inbounds i8, ptr [[FOO1]],
i64 16
+; CHECK-NEXT: store volatile i32 57005, ptr [[ADD_PTR2]], align 4
+; CHECK-NEXT: [[ADD_PTR14:%.*]] = getelementptr inbounds i8, ptr [[BAR3]],
i64 12
+; CHECK-NEXT: store volatile i32 48879, ptr [[ADD_PTR14]], align 4
+; CHECK-NEXT: ret void
+;
+entry:
+ %add.ptr = getelementptr inbounds i8, ptr addrspace(272) %foo, i64 16
+ store volatile i32 57005, ptr addrspace...
[truncated]
``````````
</details>
https://github.com/llvm/llvm-project/pull/79902
_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
