1 files changed, 206 insertions, 0 deletions
diff --git a/compiler/rustc_llvm/llvm-wrapper/CoverageMappingWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/CoverageMappingWrapper.cpp
new file mode 100644
index 00000000000..d61ec0b641c
--- /dev/null
+++ b/compiler/rustc_llvm/llvm-wrapper/CoverageMappingWrapper.cpp
@@ -0,0 +1,206 @@
+#include "LLVMWrapper.h"
+#include "llvm/ProfileData/Coverage/CoverageMapping.h"
+#include "llvm/ProfileData/Coverage/CoverageMappingWriter.h"
+#include "llvm/ProfileData/InstrProf.h"
+#include "llvm/ADT/ArrayRef.h"
+
+#include <iostream>
+
+using namespace llvm;
+
+// FFI equivalent of enum `llvm::coverage::Counter::CounterKind`
+// https://github.com/rust-lang/llvm-project/blob/ea6fa9c2/llvm/include/llvm/ProfileData/Coverage/CoverageMapping.h#L97-L99
+enum class LLVMRustCounterKind {
+  Zero = 0,
+  CounterValueReference = 1,
+  Expression = 2,
+};
+
+// FFI equivalent of struct `llvm::coverage::Counter`
+// https://github.com/rust-lang/llvm-project/blob/ea6fa9c2/llvm/include/llvm/ProfileData/Coverage/CoverageMapping.h#L94-L149
+struct LLVMRustCounter {
+  LLVMRustCounterKind CounterKind;
+  uint32_t ID;
+};
+
+static coverage::Counter fromRust(LLVMRustCounter Counter) {
+  switch (Counter.CounterKind) {
+  case LLVMRustCounterKind::Zero:
+    return coverage::Counter::getZero();
+  case LLVMRustCounterKind::CounterValueReference:
+    return coverage::Counter::getCounter(Counter.ID);
+  case LLVMRustCounterKind::Expression:
+    return coverage::Counter::getExpression(Counter.ID);
+  }
+  report_fatal_error("Bad LLVMRustCounterKind!");
+}
+
+// FFI equivalent of enum `llvm::coverage::CounterMappingRegion::RegionKind`
+// https://github.com/rust-lang/llvm-project/blob/ea6fa9c2/llvm/include/llvm/ProfileData/Coverage/CoverageMapping.h#L213-L234
+enum class LLVMRustCounterMappingRegionKind {
+  CodeRegion = 0,
+  ExpansionRegion = 1,
+  SkippedRegion = 2,
+  GapRegion = 3,
+  BranchRegion = 4,
+};
+
+static coverage::CounterMappingRegion::RegionKind
+fromRust(LLVMRustCounterMappingRegionKind Kind) {
+  switch (Kind) {
+  case LLVMRustCounterMappingRegionKind::CodeRegion:
+    return coverage::CounterMappingRegion::CodeRegion;
+  case LLVMRustCounterMappingRegionKind::ExpansionRegion:
+    return coverage::CounterMappingRegion::ExpansionRegion;
+  case LLVMRustCounterMappingRegionKind::SkippedRegion:
+    return coverage::CounterMappingRegion::SkippedRegion;
+  case LLVMRustCounterMappingRegionKind::GapRegion:
+    return coverage::CounterMappingRegion::GapRegion;
+  case LLVMRustCounterMappingRegionKind::BranchRegion:
+    return coverage::CounterMappingRegion::BranchRegion;
+  }
+  report_fatal_error("Bad LLVMRustCounterMappingRegionKind!");
+}
+
+// FFI equivalent of struct `llvm::coverage::CounterMappingRegion`
+// https://github.com/rust-lang/llvm-project/blob/ea6fa9c2/llvm/include/llvm/ProfileData/Coverage/CoverageMapping.h#L211-L304
+struct LLVMRustCounterMappingRegion {
+  LLVMRustCounter Count;
+  LLVMRustCounter FalseCount;
+  uint32_t FileID;
+  uint32_t ExpandedFileID;
+  uint32_t LineStart;
+  uint32_t ColumnStart;
+  uint32_t LineEnd;
+  uint32_t ColumnEnd;
+  LLVMRustCounterMappingRegionKind Kind;
+};
+
+// FFI equivalent of enum `llvm::coverage::CounterExpression::ExprKind`
+// https://github.com/rust-lang/llvm-project/blob/ea6fa9c2/llvm/include/llvm/ProfileData/Coverage/CoverageMapping.h#L154
+enum class LLVMRustCounterExprKind {
+  Subtract = 0,
+  Add = 1,
+};
+
+// FFI equivalent of struct `llvm::coverage::CounterExpression`
+// https://github.com/rust-lang/llvm-project/blob/ea6fa9c2/llvm/include/llvm/ProfileData/Coverage/CoverageMapping.h#L151-L160
+struct LLVMRustCounterExpression {
+  LLVMRustCounterExprKind Kind;
+  LLVMRustCounter LHS;
+  LLVMRustCounter RHS;
+};
+
+static coverage::CounterExpression::ExprKind
+fromRust(LLVMRustCounterExprKind Kind) {
+  switch (Kind) {
+  case LLVMRustCounterExprKind::Subtract:
+    return coverage::CounterExpression::Subtract;
+  case LLVMRustCounterExprKind::Add:
+    return coverage::CounterExpression::Add;
+  }
+  report_fatal_error("Bad LLVMRustCounterExprKind!");
+}
+
+extern "C" void LLVMRustCoverageWriteFilenamesSectionToBuffer(
+    const char *const Filenames[],
+    size_t FilenamesLen,
+    const size_t *const Lengths,
+    size_t LengthsLen,
+    RustStringRef BufferOut) {
+  if (FilenamesLen != LengthsLen) {
+    report_fatal_error(
+        "Mismatched lengths in LLVMRustCoverageWriteFilenamesSectionToBuffer");
+  }
+
+  SmallVector<std::string,32> FilenameRefs;
+  FilenameRefs.reserve(FilenamesLen);
+  for (size_t i = 0; i < FilenamesLen; i++) {
+    FilenameRefs.emplace_back(Filenames[i], Lengths[i]);
+  }
+  auto FilenamesWriter =
+      coverage::CoverageFilenamesSectionWriter(ArrayRef<std::string>(FilenameRefs));
+  RawRustStringOstream OS(BufferOut);
+  FilenamesWriter.write(OS);
+}
+
+extern "C" void LLVMRustCoverageWriteMappingToBuffer(
+    const unsigned *VirtualFileMappingIDs,
+    unsigned NumVirtualFileMappingIDs,
+    const LLVMRustCounterExpression *RustExpressions,
+    unsigned NumExpressions,
+    const LLVMRustCounterMappingRegion *RustMappingRegions,
+    unsigned NumMappingRegions,
+    RustStringRef BufferOut) {
+  // Convert from FFI representation to LLVM representation.
+  SmallVector<coverage::CounterMappingRegion, 0> MappingRegions;
+  MappingRegions.reserve(NumMappingRegions);
+  for (const auto &Region : ArrayRef<LLVMRustCounterMappingRegion>(
+           RustMappingRegions, NumMappingRegions)) {
+    MappingRegions.emplace_back(
+        fromRust(Region.Count), fromRust(Region.FalseCount),
+        Region.FileID, Region.ExpandedFileID,
+        Region.LineStart, Region.ColumnStart, Region.LineEnd, Region.ColumnEnd,
+        fromRust(Region.Kind));
+  }
+
+  std::vector<coverage::CounterExpression> Expressions;
+  Expressions.reserve(NumExpressions);
+  for (const auto &Expression :
+       ArrayRef<LLVMRustCounterExpression>(RustExpressions, NumExpressions)) {
+    Expressions.emplace_back(fromRust(Expression.Kind),
+                             fromRust(Expression.LHS),
+                             fromRust(Expression.RHS));
+  }
+
+  auto CoverageMappingWriter = coverage::CoverageMappingWriter(
+      ArrayRef<unsigned>(VirtualFileMappingIDs, NumVirtualFileMappingIDs),
+      Expressions,
+      MappingRegions);
+  RawRustStringOstream OS(BufferOut);
+  CoverageMappingWriter.write(OS);
+}
+
+extern "C" LLVMValueRef LLVMRustCoverageCreatePGOFuncNameVar(
+    LLVMValueRef F,
+    const char *FuncName,
+    size_t FuncNameLen) {
+  StringRef FuncNameRef(FuncName, FuncNameLen);
+  return wrap(createPGOFuncNameVar(*cast<Function>(unwrap(F)), FuncNameRef));
+}
+
+extern "C" uint64_t LLVMRustCoverageHashByteArray(
+    const char *Bytes,
+    size_t NumBytes) {
+  StringRef StrRef(Bytes, NumBytes);
+  return IndexedInstrProf::ComputeHash(StrRef);
+}
+
+static void WriteSectionNameToString(LLVMModuleRef M,
+                                     InstrProfSectKind SK,
+                                     RustStringRef Str) {
+  Triple TargetTriple(unwrap(M)->getTargetTriple());
+  auto name = getInstrProfSectionName(SK, TargetTriple.getObjectFormat());
+  RawRustStringOstream OS(Str);
+  OS << name;
+}
+
+extern "C" void LLVMRustCoverageWriteMapSectionNameToString(LLVMModuleRef M,
+                                                            RustStringRef Str) {
+  WriteSectionNameToString(M, IPSK_covmap, Str);
+}
+
+extern "C" void LLVMRustCoverageWriteFuncSectionNameToString(LLVMModuleRef M,
+                                                             RustStringRef Str) {
+  WriteSectionNameToString(M, IPSK_covfun, Str);
+}
+
+extern "C" void LLVMRustCoverageWriteMappingVarNameToString(RustStringRef Str) {
+  auto name = getCoverageMappingVarName();
+  RawRustStringOstream OS(Str);
+  OS << name;
+}
+
+extern "C" uint32_t LLVMRustCoverageMappingVersion() {
+  return coverage::CovMapVersion::Version6;
+}