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1//===-- memprof_mapping.h --------------------------------------*- C++ -*-===//2//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-exception6//7//===----------------------------------------------------------------------===//8//9// This file is a part of MemProfiler, a memory profiler.10//11// Defines MemProf memory mapping.12//===----------------------------------------------------------------------===//13#ifndef MEMPROF_MAPPING_H14#define MEMPROF_MAPPING_H15 16#include "memprof_internal.h"17 18static const u64 kDefaultShadowScale = 3;19#define SHADOW_SCALE kDefaultShadowScale20 21#define SHADOW_OFFSET __memprof_shadow_memory_dynamic_address22 23#define SHADOW_GRANULARITY (1ULL << SHADOW_SCALE)24#define MEMPROF_ALIGNMENT 3225namespace __memprof {26 27extern uptr kHighMemEnd; // Initialized in __memprof_init.28 29} // namespace __memprof30 31// Size of memory block mapped to a single shadow location32#define MEM_GRANULARITY 64ULL33 34#define SHADOW_MASK ~(MEM_GRANULARITY - 1)35 36#define MEM_TO_SHADOW(mem) \37 ((((mem) & SHADOW_MASK) >> SHADOW_SCALE) + (SHADOW_OFFSET))38 39// Histogram shadow memory is laid different to the standard configuration:40 41// 8 bytes42// +---+---+---+ +---+---+---+ +---+---+---+43// Memory | a | | b | | c |44// +---+---+---+ +---+---+---+ +---+---+---+45 46// +---+ +---+ +---+47// Shadow | a | | b | | c |48// +---+ +---+ +---+49// 1 byte50//51// Where we have a 1 byte counter for each 8 bytes. HISTOGRAM_MEM_TO_SHADOW52// translates a memory address to the address of its corresponding shadow53// counter memory address. The same data is still provided in MIB whether54// histograms are used or not. Total access counts per allocations are55// computed by summing up all individual 1 byte counters. This can incur an56// accuracy penalty.57 58#define HISTOGRAM_GRANULARITY 8ULL59 60#define HISTOGRAM_MAX_COUNTER 255U61 62#define HISTOGRAM_SHADOW_MASK ~(HISTOGRAM_GRANULARITY - 1)63 64#define HISTOGRAM_MEM_TO_SHADOW(mem) \65 ((((mem) & HISTOGRAM_SHADOW_MASK) >> SHADOW_SCALE) + (SHADOW_OFFSET))66 67#define SHADOW_ENTRY_SIZE (MEM_GRANULARITY >> SHADOW_SCALE)68 69#define kLowMemBeg 070#define kLowMemEnd (SHADOW_OFFSET ? SHADOW_OFFSET - 1 : 0)71 72#define kLowShadowBeg SHADOW_OFFSET73#define kLowShadowEnd (MEM_TO_SHADOW(kLowMemEnd) + SHADOW_ENTRY_SIZE - 1)74 75#define kHighMemBeg (MEM_TO_SHADOW(kHighMemEnd) + 1 + SHADOW_ENTRY_SIZE - 1)76 77#define kHighShadowBeg MEM_TO_SHADOW(kHighMemBeg)78#define kHighShadowEnd (MEM_TO_SHADOW(kHighMemEnd) + SHADOW_ENTRY_SIZE - 1)79 80// With the zero shadow base we can not actually map pages starting from 0.81// This constant is somewhat arbitrary.82#define kZeroBaseShadowStart 083#define kZeroBaseMaxShadowStart (1 << 18)84 85#define kShadowGapBeg (kLowShadowEnd ? kLowShadowEnd + 1 : kZeroBaseShadowStart)86#define kShadowGapEnd (kHighShadowBeg - 1)87 88namespace __memprof {89 90inline uptr MemToShadowSize(uptr size) { return size >> SHADOW_SCALE; }91inline bool AddrIsInLowMem(uptr a) { return a <= kLowMemEnd; }92 93inline bool AddrIsInLowShadow(uptr a) {94 return a >= kLowShadowBeg && a <= kLowShadowEnd;95}96 97inline bool AddrIsInHighMem(uptr a) {98 return kHighMemBeg && a >= kHighMemBeg && a <= kHighMemEnd;99}100 101inline bool AddrIsInHighShadow(uptr a) {102 return kHighMemBeg && a >= kHighShadowBeg && a <= kHighShadowEnd;103}104 105inline bool AddrIsInShadowGap(uptr a) {106 // In zero-based shadow mode we treat addresses near zero as addresses107 // in shadow gap as well.108 if (SHADOW_OFFSET == 0)109 return a <= kShadowGapEnd;110 return a >= kShadowGapBeg && a <= kShadowGapEnd;111}112 113inline bool AddrIsInMem(uptr a) {114 return AddrIsInLowMem(a) || AddrIsInHighMem(a) ||115 (flags()->protect_shadow_gap == 0 && AddrIsInShadowGap(a));116}117 118inline uptr MemToShadow(uptr p) {119 CHECK(AddrIsInMem(p));120 return MEM_TO_SHADOW(p);121}122 123inline bool AddrIsInShadow(uptr a) {124 return AddrIsInLowShadow(a) || AddrIsInHighShadow(a);125}126 127inline bool AddrIsAlignedByGranularity(uptr a) {128 return (a & (SHADOW_GRANULARITY - 1)) == 0;129}130 131inline void RecordAccess(uptr a) {132 // If we use a different shadow size then the type below needs adjustment.133 CHECK_EQ(SHADOW_ENTRY_SIZE, 8);134 u64 *shadow_address = (u64 *)MEM_TO_SHADOW(a);135 (*shadow_address)++;136}137 138inline void RecordAccessHistogram(uptr a) {139 CHECK_EQ(SHADOW_ENTRY_SIZE, 8);140 u8 *shadow_address = (u8 *)HISTOGRAM_MEM_TO_SHADOW(a);141 if (*shadow_address < HISTOGRAM_MAX_COUNTER) {142 (*shadow_address)++;143 }144}145 146} // namespace __memprof147 148#endif // MEMPROF_MAPPING_H149