bpftrace/SOURCES/bpftrace-0.16.0-IR-builder-...

458 lines
20 KiB
Diff

From dfc1f92653707c8d11bdb3be98e68f8297b9bc71 Mon Sep 17 00:00:00 2001
From: Viktor Malik <viktor.malik@gmail.com>
Date: Mon, 10 Oct 2022 14:26:38 +0200
Subject: [PATCH] IR builder: get rid of getPointerElementType calls
Usage of Value::getPointerElementType is deprecated and will be dropped
in LLVM 16 [1].
There are several places where we use this method:
- function (value) calls - the called function type is usually
available, so just pass it to createCall, the only exception is
CreateProbeReadStr which must have been refactored
- getting the type of alloca instruction - there is a dedicated
AllocaInst::getAllocatedType method that can be used instead
- strncmp - pass sizes of the strings to CreateStrncmp to be able to get
the correct string type (which is array of uint8)
[1] https://llvm.org/docs/OpaquePointers.html
---
src/ast/irbuilderbpf.cpp | 143 ++++++++++++--------------------
src/ast/irbuilderbpf.h | 23 +++--
src/ast/passes/codegen_llvm.cpp | 30 +++++--
3 files changed, 86 insertions(+), 110 deletions(-)
diff --git a/src/ast/irbuilderbpf.cpp b/src/ast/irbuilderbpf.cpp
index d49883f7..4036b2df 100644
--- a/src/ast/irbuilderbpf.cpp
+++ b/src/ast/irbuilderbpf.cpp
@@ -288,17 +288,16 @@ CallInst *IRBuilderBPF::CreateHelperCall(libbpf::bpf_func_id func_id,
Constant *helper_func = ConstantExpr::getCast(Instruction::IntToPtr,
getInt64(func_id),
helper_ptr_type);
- return createCall(helper_func, args, Name);
+ return createCall(helper_type, helper_func, args, Name);
}
-CallInst *IRBuilderBPF::createCall(Value *callee,
+CallInst *IRBuilderBPF::createCall(FunctionType *callee_type,
+ Value *callee,
ArrayRef<Value *> args,
const Twine &Name)
{
#if LLVM_VERSION_MAJOR >= 11
- auto *calleePtrType = cast<PointerType>(callee->getType());
- auto *calleeType = cast<FunctionType>(calleePtrType->getPointerElementType());
- return CreateCall(calleeType, callee, args, Name);
+ return CreateCall(callee_type, callee, args, Name);
#else
return CreateCall(callee, args, Name);
#endif
@@ -307,7 +306,7 @@ CallInst *IRBuilderBPF::createCall(Value *callee,
CallInst *IRBuilderBPF::CreateBpfPseudoCallId(int mapid)
{
Function *pseudo_func = module_.getFunction("llvm.bpf.pseudo");
- return createCall(pseudo_func,
+ return CreateCall(pseudo_func,
{ getInt64(BPF_PSEUDO_MAP_FD), getInt64(mapid) },
"pseudo");
}
@@ -346,7 +345,8 @@ CallInst *IRBuilderBPF::createMapLookup(int mapid, Value *key)
Instruction::IntToPtr,
getInt64(libbpf::BPF_FUNC_map_lookup_elem),
lookup_func_ptr_type);
- return createCall(lookup_func, { map_ptr, key }, "lookup_elem");
+ return createCall(
+ lookup_func_type, lookup_func, { map_ptr, key }, "lookup_elem");
}
CallInst *IRBuilderBPF::CreateGetJoinMap(Value *ctx, const location &loc)
@@ -397,8 +397,7 @@ Value *IRBuilderBPF::CreateMapLookupElem(Value *ctx,
CREATE_MEMCPY(value, call, type.GetSize(), 1);
else
{
- assert(value->getType()->isPointerTy() &&
- (value->getType()->getPointerElementType() == getInt64Ty()));
+ assert(value->getAllocatedType() == getInt64Ty());
// createMapLookup returns an u8*
auto *cast = CreatePointerCast(call, value->getType(), "cast");
CreateStore(CreateLoad(getInt64Ty(), cast), value);
@@ -448,7 +447,8 @@ void IRBuilderBPF::CreateMapUpdateElem(Value *ctx,
Instruction::IntToPtr,
getInt64(libbpf::BPF_FUNC_map_update_elem),
update_func_ptr_type);
- CallInst *call = createCall(update_func,
+ CallInst *call = createCall(update_func_type,
+ update_func,
{ map_ptr, key, val, flags },
"update_elem");
CreateHelperErrorCond(ctx, call, libbpf::BPF_FUNC_map_update_elem, loc);
@@ -472,7 +472,8 @@ void IRBuilderBPF::CreateMapDeleteElem(Value *ctx,
Instruction::IntToPtr,
getInt64(libbpf::BPF_FUNC_map_delete_elem),
delete_func_ptr_type);
- CallInst *call = createCall(delete_func, { map_ptr, key }, "delete_elem");
+ CallInst *call = createCall(
+ delete_func_type, delete_func, { map_ptr, key }, "delete_elem");
CreateHelperErrorCond(ctx, call, libbpf::BPF_FUNC_map_delete_elem, loc);
}
@@ -508,72 +509,53 @@ void IRBuilderBPF::CreateProbeRead(Value *ctx,
Constant *proberead_func = ConstantExpr::getCast(Instruction::IntToPtr,
getInt64(read_fn),
proberead_func_ptr_type);
- CallInst *call = createCall(proberead_func,
+ CallInst *call = createCall(proberead_func_type,
+ proberead_func,
{ dst, size, src },
probeReadHelperName(read_fn));
CreateHelperErrorCond(ctx, call, read_fn, loc);
}
-Constant *IRBuilderBPF::createProbeReadStrFn(llvm::Type *dst,
- llvm::Type *src,
- AddrSpace as)
-{
- assert(src && (src->isIntegerTy() || src->isPointerTy()));
- // int bpf_probe_read_str(void *dst, int size, const void *unsafe_ptr)
- FunctionType *probereadstr_func_type = FunctionType::get(
- getInt64Ty(), { dst, getInt32Ty(), src }, false);
- PointerType *probereadstr_func_ptr_type = PointerType::get(
- probereadstr_func_type, 0);
- return ConstantExpr::getCast(Instruction::IntToPtr,
- getInt64(selectProbeReadHelper(as, true)),
- probereadstr_func_ptr_type);
-}
-
CallInst *IRBuilderBPF::CreateProbeReadStr(Value *ctx,
- AllocaInst *dst,
+ Value *dst,
size_t size,
Value *src,
AddrSpace as,
const location &loc)
{
- assert(ctx && ctx->getType() == getInt8PtrTy());
return CreateProbeReadStr(ctx, dst, getInt32(size), src, as, loc);
}
CallInst *IRBuilderBPF::CreateProbeReadStr(Value *ctx,
Value *dst,
- size_t size,
- Value *src,
- AddrSpace as,
- const location &loc)
-{
- assert(ctx && ctx->getType() == getInt8PtrTy());
- Constant *fn = createProbeReadStrFn(dst->getType(), src->getType(), as);
- auto read_fn = selectProbeReadHelper(as, true);
- CallInst *call = createCall(fn,
- { dst, getInt32(size), src },
- probeReadHelperName(read_fn));
- CreateHelperErrorCond(ctx, call, read_fn, loc);
- return call;
-}
-
-CallInst *IRBuilderBPF::CreateProbeReadStr(Value *ctx,
- AllocaInst *dst,
llvm::Value *size,
Value *src,
AddrSpace as,
const location &loc)
{
assert(ctx && ctx->getType() == getInt8PtrTy());
- assert(dst && dst->getAllocatedType()->isArrayTy() &&
- dst->getAllocatedType()->getArrayElementType() == getInt8Ty());
assert(size && size->getType()->isIntegerTy());
+ if (auto *dst_alloca = dyn_cast<AllocaInst>(dst))
+ {
+ assert(dst_alloca->getAllocatedType()->isArrayTy() &&
+ dst_alloca->getAllocatedType()->getArrayElementType() ==
+ getInt8Ty());
+ }
- auto *size_i32 = CreateIntCast(size, getInt32Ty(), false);
+ auto *size_i32 = size;
+ if (size_i32->getType()->getScalarSizeInBits() != 32)
+ size_i32 = CreateIntCast(size_i32, getInt32Ty(), false);
- Constant *fn = createProbeReadStrFn(dst->getType(), src->getType(), as);
auto read_fn = selectProbeReadHelper(as, true);
- CallInst *call = createCall(fn,
+ // int bpf_probe_read_str(void *dst, int size, const void *unsafe_ptr)
+ FunctionType *probereadstr_func_type = FunctionType::get(
+ getInt64Ty(), { dst->getType(), getInt32Ty(), src->getType() }, false);
+ PointerType *probereadstr_func_ptr_type = PointerType::get(
+ probereadstr_func_type, 0);
+ Constant *probereadstr_callee = ConstantExpr::getCast(
+ Instruction::IntToPtr, getInt64(read_fn), probereadstr_func_ptr_type);
+ CallInst *call = createCall(probereadstr_func_type,
+ probereadstr_callee,
{ dst, size_i32, src },
probeReadHelperName(read_fn));
CreateHelperErrorCond(ctx, call, read_fn, loc);
@@ -732,8 +714,10 @@ Value *IRBuilderBPF::CreateUSDTReadArgument(Value *ctx,
return result;
}
-Value *IRBuilderBPF::CreateStrncmp(Value *val1,
- Value *val2,
+Value *IRBuilderBPF::CreateStrncmp(Value *str1,
+ uint64_t str1_size,
+ Value *str2,
+ uint64_t str2_size,
uint64_t n,
bool inverse)
{
@@ -762,40 +746,21 @@ Value *IRBuilderBPF::CreateStrncmp(Value *val1,
// Check if the compared strings are literals.
// If so, we can avoid storing the literal in memory.
std::optional<std::string> literal1;
- if (auto constString1 = dyn_cast<ConstantDataArray>(val1))
+ if (auto constString1 = dyn_cast<ConstantDataArray>(str1))
literal1 = constString1->getAsString();
- else if (isa<ConstantAggregateZero>(val1))
+ else if (isa<ConstantAggregateZero>(str1))
literal1 = "";
else
literal1 = std::nullopt;
std::optional<std::string> literal2;
- if (auto constString2 = dyn_cast<ConstantDataArray>(val2))
+ if (auto constString2 = dyn_cast<ConstantDataArray>(str2))
literal2 = constString2->getAsString();
- else if (isa<ConstantAggregateZero>(val2))
+ else if (isa<ConstantAggregateZero>(str2))
literal2 = "";
else
literal2 = std::nullopt;
- auto *val1p = dyn_cast<PointerType>(val1->getType());
- auto *val2p = dyn_cast<PointerType>(val2->getType());
-#ifndef NDEBUG
- if (!literal1)
- {
- assert(val1p);
- assert(val1p->getPointerElementType()->isArrayTy() &&
- val1p->getPointerElementType()->getArrayElementType() ==
- getInt8Ty());
- }
- if (!literal2)
- {
- assert(val2p);
- assert(val2p->getPointerElementType()->isArrayTy() &&
- val2p->getPointerElementType()->getArrayElementType() ==
- getInt8Ty());
- }
-#endif
-
Function *parent = GetInsertBlock()->getParent();
AllocaInst *store = CreateAllocaBPF(getInt1Ty(), "strcmp.result");
BasicBlock *str_ne = BasicBlock::Create(module_.getContext(),
@@ -822,8 +787,8 @@ Value *IRBuilderBPF::CreateStrncmp(Value *val1,
l = getInt8(literal1->c_str()[i]);
else
{
- auto *ptr_l = CreateGEP(val1p->getPointerElementType(),
- val1,
+ auto *ptr_l = CreateGEP(ArrayType::get(getInt8Ty(), str1_size),
+ str1,
{ getInt32(0), getInt32(i) });
l = CreateLoad(getInt8Ty(), ptr_l);
}
@@ -833,8 +798,8 @@ Value *IRBuilderBPF::CreateStrncmp(Value *val1,
r = getInt8(literal2->c_str()[i]);
else
{
- auto *ptr_r = CreateGEP(val2p->getPointerElementType(),
- val2,
+ auto *ptr_r = CreateGEP(ArrayType::get(getInt8Ty(), str2_size),
+ str2,
{ getInt32(0), getInt32(i) });
r = CreateLoad(getInt8Ty(), ptr_r);
}
@@ -994,11 +959,9 @@ void IRBuilderBPF::CreateGetCurrentComm(Value *ctx,
size_t size,
const location &loc)
{
- assert(buf->getType()->getPointerElementType()->isArrayTy() &&
- buf->getType()->getPointerElementType()->getArrayNumElements() >=
- size &&
- buf->getType()->getPointerElementType()->getArrayElementType() ==
- getInt8Ty());
+ assert(buf->getAllocatedType()->isArrayTy() &&
+ buf->getAllocatedType()->getArrayNumElements() >= size &&
+ buf->getAllocatedType()->getArrayElementType() == getInt8Ty());
// long bpf_get_current_comm(char *buf, int size_of_buf)
// Return: 0 on success or negative error
@@ -1077,7 +1040,7 @@ void IRBuilderBPF::CreateSignal(Value *ctx, Value *sig, const location &loc)
Instruction::IntToPtr,
getInt64(libbpf::BPF_FUNC_send_signal),
signal_func_ptr_type);
- CallInst *call = createCall(signal_func, { sig }, "signal");
+ CallInst *call = createCall(signal_func_type, signal_func, { sig }, "signal");
CreateHelperErrorCond(ctx, call, libbpf::BPF_FUNC_send_signal, loc);
}
@@ -1091,7 +1054,7 @@ void IRBuilderBPF::CreateOverrideReturn(Value *ctx, Value *rc)
Constant *override_func = ConstantExpr::getCast(Instruction::IntToPtr,
getInt64(libbpf::BPF_FUNC_override_return),
override_func_ptr_type);
- createCall(override_func, { ctx, rc }, "override");
+ createCall(override_func_type, override_func, { ctx, rc }, "override");
}
CallInst *IRBuilderBPF::CreateSkbOutput(Value *skb,
@@ -1126,7 +1089,8 @@ CallInst *IRBuilderBPF::CreateSkbOutput(Value *skb,
Instruction::IntToPtr,
getInt64(libbpf::BPF_FUNC_skb_output),
skb_output_func_ptr_type);
- CallInst *call = createCall(skb_output_func,
+ CallInst *call = createCall(skb_output_func_type,
+ skb_output_func,
{ skb, map_ptr, flags, data, size_val },
"skb_output");
return call;
@@ -1320,7 +1284,8 @@ void IRBuilderBPF::CreateSeqPrintf(Value *ctx,
CreateGEP(getInt64Ty(), meta, getInt64(0)),
"seq");
- CallInst *call = createCall(seq_printf_func,
+ CallInst *call = createCall(seq_printf_func_type,
+ seq_printf_func,
{ seq, fmt, fmt_size, data, data_len },
"seq_printf");
CreateHelperErrorCond(ctx, call, libbpf::BPF_FUNC_seq_printf, loc);
diff --git a/src/ast/irbuilderbpf.h b/src/ast/irbuilderbpf.h
index e124911b..c9ffb545 100644
--- a/src/ast/irbuilderbpf.h
+++ b/src/ast/irbuilderbpf.h
@@ -90,17 +90,11 @@ public:
AddrSpace as,
const location &loc);
CallInst *CreateProbeReadStr(Value *ctx,
- AllocaInst *dst,
+ Value *dst,
llvm::Value *size,
Value *src,
AddrSpace as,
const location &loc);
- CallInst *CreateProbeReadStr(Value *ctx,
- AllocaInst *dst,
- size_t size,
- Value *src,
- AddrSpace as,
- const location &loc);
CallInst *CreateProbeReadStr(Value *ctx,
Value *dst,
size_t size,
@@ -115,7 +109,12 @@ public:
pid_t pid,
AddrSpace as,
const location &loc);
- Value *CreateStrncmp(Value *val1, Value *val2, uint64_t n, bool inverse);
+ Value *CreateStrncmp(Value *str1,
+ uint64_t str1_size,
+ Value *str2,
+ uint64_t str2_size,
+ uint64_t n,
+ bool inverse);
CallInst *CreateGetNs(bool boot_time, const location &loc);
CallInst *CreateGetPidTgid(const location &loc);
CallInst *CreateGetCurrentCgroupId(const location &loc);
@@ -131,7 +130,10 @@ public:
ArrayRef<Value *> args,
const Twine &Name,
const location *loc = nullptr);
- CallInst *createCall(Value *callee, ArrayRef<Value *> args, const Twine &Name);
+ CallInst *createCall(FunctionType *callee_type,
+ Value *callee,
+ ArrayRef<Value *> args,
+ const Twine &Name);
void CreateGetCurrentComm(Value *ctx, AllocaInst *buf, size_t size, const location& loc);
void CreatePerfEventOutput(Value *ctx,
Value *data,
@@ -185,9 +187,6 @@ private:
AddrSpace as,
const location &loc);
CallInst *createMapLookup(int mapid, Value *key);
- Constant *createProbeReadStrFn(llvm::Type *dst,
- llvm::Type *src,
- AddrSpace as);
libbpf::bpf_func_id selectProbeReadHelper(AddrSpace as, bool str);
std::map<std::string, StructType *> structs_;
diff --git a/src/ast/passes/codegen_llvm.cpp b/src/ast/passes/codegen_llvm.cpp
index a818ca0b..2b888087 100644
--- a/src/ast/passes/codegen_llvm.cpp
+++ b/src/ast/passes/codegen_llvm.cpp
@@ -1133,8 +1133,12 @@ void CodegenLLVM::visit(Call &call)
auto left_string = getString(left_arg);
auto right_string = getString(right_arg);
- expr_ = b_.CreateStrncmp(
- left_string.first, right_string.first, size, false);
+ expr_ = b_.CreateStrncmp(left_string.first,
+ left_string.second,
+ right_string.first,
+ right_string.second,
+ size,
+ false);
}
else if (call.func == "override")
{
@@ -1269,8 +1273,7 @@ void CodegenLLVM::visit(Variable &var)
else
{
auto *var_alloca = variables_[var.ident];
- expr_ = b_.CreateLoad(var_alloca->getType()->getPointerElementType(),
- var_alloca);
+ expr_ = b_.CreateLoad(var_alloca->getAllocatedType(), var_alloca);
}
}
@@ -1310,7 +1313,12 @@ void CodegenLLVM::binop_string(Binop &binop)
auto right_string = getString(binop.right);
size_t len = std::min(left_string.second, right_string.second);
- expr_ = b_.CreateStrncmp(left_string.first, right_string.first, len, inverse);
+ expr_ = b_.CreateStrncmp(left_string.first,
+ left_string.second,
+ right_string.first,
+ right_string.second,
+ len,
+ inverse);
}
void CodegenLLVM::binop_buf(Binop &binop)
@@ -1334,7 +1342,12 @@ void CodegenLLVM::binop_buf(Binop &binop)
size_t len = std::min(binop.left->type.GetSize(),
binop.right->type.GetSize());
- expr_ = b_.CreateStrncmp(left_string, right_string, len, inverse);
+ expr_ = b_.CreateStrncmp(left_string,
+ binop.left->type.GetSize(),
+ right_string,
+ binop.right->type.GetSize(),
+ len,
+ inverse);
}
void CodegenLLVM::binop_int(Binop &binop)
@@ -3528,9 +3541,8 @@ void CodegenLLVM::createIncDec(Unop &unop)
else if (unop.expr->is_variable)
{
Variable &var = static_cast<Variable &>(*unop.expr);
- Value *oldval = b_.CreateLoad(
- variables_[var.ident]->getType()->getPointerElementType(),
- variables_[var.ident]);
+ Value *oldval = b_.CreateLoad(variables_[var.ident]->getAllocatedType(),
+ variables_[var.ident]);
Value *newval;
if (is_increment)
newval = b_.CreateAdd(oldval, b_.GetIntSameSize(step, oldval));
--
2.38.1