1 //===- NVVMIntrRange.cpp - Set !range metadata for NVVM intrinsics --------===//
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //===----------------------------------------------------------------------===//
9 // This pass adds appropriate !range metadata for calls to NVVM
10 // intrinsics that return a limited range of values.
12 //===----------------------------------------------------------------------===//
15 #include "llvm/IR/Constants.h"
16 #include "llvm/IR/InstIterator.h"
17 #include "llvm/IR/Instructions.h"
18 #include "llvm/IR/Intrinsics.h"
22 #define DEBUG_TYPE "nvvm-intr-range"
24 namespace llvm { void initializeNVVMIntrRangePass(PassRegistry &); }
26 // Add !range metadata based on limits of given SM variant.
27 static cl::opt<unsigned> NVVMIntrRangeSM("nvvm-intr-range-sm", cl::init(20),
28 cl::Hidden, cl::desc("SM variant"));
31 class NVVMIntrRange : public FunctionPass {
35 } MaxBlockSize, MaxGridSize;
39 NVVMIntrRange() : NVVMIntrRange(NVVMIntrRangeSM) {}
40 NVVMIntrRange(unsigned int SmVersion) : FunctionPass(ID) {
41 MaxBlockSize.x = 1024;
42 MaxBlockSize.y = 1024;
45 MaxGridSize.x = SmVersion >= 30 ? 0x7fffffff : 0xffff;
46 MaxGridSize.y = 0xffff;
47 MaxGridSize.z = 0xffff;
49 initializeNVVMIntrRangePass(*PassRegistry::getPassRegistry());
52 bool runOnFunction(Function &) override;
56 FunctionPass *llvm::createNVVMIntrRangePass(unsigned int SmVersion) {
57 return new NVVMIntrRange(SmVersion);
60 char NVVMIntrRange::ID = 0;
61 INITIALIZE_PASS(NVVMIntrRange, "nvvm-intr-range",
62 "Add !range metadata to NVVM intrinsics.", false, false)
64 // Adds the passed-in [Low,High) range information as metadata to the
65 // passed-in call instruction.
66 static bool addRangeMetadata(uint64_t Low, uint64_t High, CallInst *C) {
67 // This call already has range metadata, nothing to do.
68 if (C->getMetadata(LLVMContext::MD_range))
71 LLVMContext &Context = C->getParent()->getContext();
72 IntegerType *Int32Ty = Type::getInt32Ty(Context);
73 Metadata *LowAndHigh[] = {
74 ConstantAsMetadata::get(ConstantInt::get(Int32Ty, Low)),
75 ConstantAsMetadata::get(ConstantInt::get(Int32Ty, High))};
76 C->setMetadata(LLVMContext::MD_range, MDNode::get(Context, LowAndHigh));
80 bool NVVMIntrRange::runOnFunction(Function &F) {
81 // Go through the calls in this function.
83 for (Instruction &I : instructions(F)) {
84 CallInst *Call = dyn_cast<CallInst>(&I);
88 if (Function *Callee = Call->getCalledFunction()) {
89 switch (Callee->getIntrinsicID()) {
91 case Intrinsic::nvvm_read_ptx_sreg_tid_x:
92 Changed |= addRangeMetadata(0, MaxBlockSize.x, Call);
94 case Intrinsic::nvvm_read_ptx_sreg_tid_y:
95 Changed |= addRangeMetadata(0, MaxBlockSize.y, Call);
97 case Intrinsic::nvvm_read_ptx_sreg_tid_z:
98 Changed |= addRangeMetadata(0, MaxBlockSize.z, Call);
102 case Intrinsic::nvvm_read_ptx_sreg_ntid_x:
103 Changed |= addRangeMetadata(1, MaxBlockSize.x+1, Call);
105 case Intrinsic::nvvm_read_ptx_sreg_ntid_y:
106 Changed |= addRangeMetadata(1, MaxBlockSize.y+1, Call);
108 case Intrinsic::nvvm_read_ptx_sreg_ntid_z:
109 Changed |= addRangeMetadata(1, MaxBlockSize.z+1, Call);
113 case Intrinsic::nvvm_read_ptx_sreg_ctaid_x:
114 Changed |= addRangeMetadata(0, MaxGridSize.x, Call);
116 case Intrinsic::nvvm_read_ptx_sreg_ctaid_y:
117 Changed |= addRangeMetadata(0, MaxGridSize.y, Call);
119 case Intrinsic::nvvm_read_ptx_sreg_ctaid_z:
120 Changed |= addRangeMetadata(0, MaxGridSize.z, Call);
124 case Intrinsic::nvvm_read_ptx_sreg_nctaid_x:
125 Changed |= addRangeMetadata(1, MaxGridSize.x+1, Call);
127 case Intrinsic::nvvm_read_ptx_sreg_nctaid_y:
128 Changed |= addRangeMetadata(1, MaxGridSize.y+1, Call);
130 case Intrinsic::nvvm_read_ptx_sreg_nctaid_z:
131 Changed |= addRangeMetadata(1, MaxGridSize.z+1, Call);
134 // warp size is constant 32.
135 case Intrinsic::nvvm_read_ptx_sreg_warpsize:
136 Changed |= addRangeMetadata(32, 32+1, Call);
139 // Lane ID is [0..warpsize)
140 case Intrinsic::nvvm_read_ptx_sreg_laneid:
141 Changed |= addRangeMetadata(0, 32, Call);