1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
|
//===- PreISelIntrinsicLowering.cpp - Pre-ISel intrinsic lowering pass ----===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This pass implements IR lowering for the llvm.load.relative intrinsic.
//
//===----------------------------------------------------------------------===//
#include "llvm/CodeGen/PreISelIntrinsicLowering.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Type.h"
#include "llvm/IR/User.h"
#include "llvm/Pass.h"
#include "llvm/Support/Casting.h"
using namespace llvm;
static bool lowerLoadRelative(Function &F) {
if (F.use_empty())
return false;
bool Changed = false;
Type *Int32Ty = Type::getInt32Ty(F.getContext());
Type *Int32PtrTy = Int32Ty->getPointerTo();
Type *Int8Ty = Type::getInt8Ty(F.getContext());
for (auto I = F.use_begin(), E = F.use_end(); I != E;) {
auto CI = dyn_cast<CallInst>(I->getUser());
++I;
if (!CI || CI->getCalledValue() != &F)
continue;
IRBuilder<> B(CI);
Value *OffsetPtr =
B.CreateGEP(Int8Ty, CI->getArgOperand(0), CI->getArgOperand(1));
Value *OffsetPtrI32 = B.CreateBitCast(OffsetPtr, Int32PtrTy);
Value *OffsetI32 = B.CreateAlignedLoad(OffsetPtrI32, 4);
Value *ResultPtr = B.CreateGEP(Int8Ty, CI->getArgOperand(0), OffsetI32);
CI->replaceAllUsesWith(ResultPtr);
CI->eraseFromParent();
Changed = true;
}
return Changed;
}
static bool lowerIntrinsics(Module &M) {
bool Changed = false;
for (Function &F : M) {
if (F.getName().startswith("llvm.load.relative."))
Changed |= lowerLoadRelative(F);
}
return Changed;
}
namespace {
class PreISelIntrinsicLoweringLegacyPass : public ModulePass {
public:
static char ID;
PreISelIntrinsicLoweringLegacyPass() : ModulePass(ID) {}
bool runOnModule(Module &M) override { return lowerIntrinsics(M); }
};
} // end anonymous namespace
char PreISelIntrinsicLoweringLegacyPass::ID;
INITIALIZE_PASS(PreISelIntrinsicLoweringLegacyPass,
"pre-isel-intrinsic-lowering", "Pre-ISel Intrinsic Lowering",
false, false)
ModulePass *llvm::createPreISelIntrinsicLoweringPass() {
return new PreISelIntrinsicLoweringLegacyPass;
}
PreservedAnalyses PreISelIntrinsicLoweringPass::run(Module &M,
ModuleAnalysisManager &AM) {
if (!lowerIntrinsics(M))
return PreservedAnalyses::all();
else
return PreservedAnalyses::none();
}
|
