Index: llvm/trunk/docs/CommandGuide/llvm-cov.rst
===================================================================
--- llvm/trunk/docs/CommandGuide/llvm-cov.rst
+++ llvm/trunk/docs/CommandGuide/llvm-cov.rst
@@ -24,6 +24,7 @@
 * :ref:`gcov <llvm-cov-gcov>`
 * :ref:`show <llvm-cov-show>`
 * :ref:`report <llvm-cov-report>`
+* :ref:`export <llvm-cov-export>`
 
 .. program:: llvm-cov gcov
 
@@ -315,3 +316,31 @@
  It is an error to specify an architecture that is not included in the
  universal binary or to use an architecture that does not match a
  non-universal binary.
+
+EXPORT COMMAND
+--------------
+
+SYNOPSIS
+^^^^^^^^
+
+:program:`llvm-cov export` [*options*] -instr-profile *PROFILE* *BIN*
+
+DESCRIPTION
+^^^^^^^^^^^
+
+The :program:`llvm-cov export` command exports regions, functions, expansions,
+and summaries of the coverage of a binary *BIN* using the profile data
+*PROFILE* as JSON.
+
+For information on compiling programs for coverage and generating profile data,
+see :ref:`llvm-cov-show`.
+
+OPTIONS
+^^^^^^^
+
+.. option:: -arch=<name>
+
+ If the covered binary is a universal binary, select the architecture to use.
+ It is an error to specify an architecture that is not included in the
+ universal binary or to use an architecture that does not match a
+ non-universal binary.
Index: llvm/trunk/test/tools/llvm-cov/Inputs/binary-formats.canonical.json
===================================================================
--- llvm/trunk/test/tools/llvm-cov/Inputs/binary-formats.canonical.json
+++ llvm/trunk/test/tools/llvm-cov/Inputs/binary-formats.canonical.json
@@ -0,0 +1,38 @@
+// Metadata section
+// CHECK: {"version":"1.0.0","type":"llvm.coverage.json.export","data":[
+
+// Open Export
+// CHECK-SAME: {"object":"{{[^\"]+}}","files":[
+
+// File Object
+// CHECK-SAME: {"filename":"{{[^\"]+}}/binary-formats.c",
+// CHECK-SAME: "segments":[
+// CHECK-SAME: [4,40,100,1,1],[4,42,0,0,0]],
+// CHECK-SAME: "expansions":[],
+
+// Verify the Summary Section for the first file
+// CHECK-SAME: "summary":{
+// CHECK-SAME: "lines":{"count":1,"covered":1,"percent":100,"noncode":0},
+// CHECK-SAME: "functions":{"count":1,"covered":1,"percent":100},
+// CHECK-SAME: "regions":{"count":1,"covered":1,"notcovered":0,"percent":100}}}
+
+// Close Files Array
+// CHECK-SAME: ],
+
+// Functions List
+// CHECK-SAME: "functions":[
+// CHECK-SAME: {"name":"main","count":100,"regions":[
+// CHECK-SAME: [4,40,4,42,100,0,0,0]
+// CHECK-SAME: ],
+// CHECK-SAME: "filenames":["{{[^\"]+}}/binary-formats.c"]
+// CHECK-SAME: }],
+
+
+// Full Export Summary
+// CHECK-SAME: "totals":{
+// CHECK-SAME: "lines":{"count":1,"covered":1,"percent":100,"noncode":0},
+// CHECK-SAME: "functions":{"count":1,"covered":1,"percent":100},
+// CHECK-SAME: "regions":{"count":1,"covered":1,"notcovered":0,"percent":100}}
+
+// Close the export object, data array, and root object
+// CHECK-SAME: }]}
Index: llvm/trunk/test/tools/llvm-cov/Inputs/highlightedRanges.json
===================================================================
--- llvm/trunk/test/tools/llvm-cov/Inputs/highlightedRanges.json
+++ llvm/trunk/test/tools/llvm-cov/Inputs/highlightedRanges.json
@@ -0,0 +1,53 @@
+// Metadata section
+// CHECK: {"version":"1.0.0","type":"llvm.coverage.json.export","data":[
+
+// Open Export
+// CHECK-SAME: {"object":"{{[^\"]+}}","files":[
+
+// File Object
+// CHECK-SAME: {"filename":"{{[^\"]+}}/showHighlightedRanges.cpp",
+// CHECK-SAME: "segments":[
+// CHECK-SAME: {{(\[[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+\],?)+}}],
+// CHECK-SAME: "expansions":[],
+
+// Verify the Summary Section for the first file
+// CHECK-SAME: "summary":{
+// CHECK-SAME: "lines":{"count":40,"covered":26,"percent":65,"noncode":0},
+// CHECK-SAME: "functions":{"count":4,"covered":4,"percent":100},
+// CHECK-SAME: "regions":{"count":19,"covered":11,"notcovered":8,"percent":57}}}
+
+// Close Files Array
+// CHECK-SAME: ],
+
+// Functions List
+// CHECK-SAME: "functions":[
+// CHECK-SAME: {"name":"_Z4funcv","count":1,"regions":[
+// CHECK-SAME: {{(\[[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+\],?)+}}
+// CHECK-SAME: ],
+// CHECK-SAME: "filenames":["{{[^\"]+}}/showHighlightedRanges.cpp"]
+// CHECK-SAME: }
+// CHECK-SAME: {"name":"_Z5func2i","count":1,"regions":[
+// CHECK-SAME: {{(\[[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+\],?)+}}
+// CHECK-SAME: ],
+// CHECK-SAME: "filenames":["{{[^\"]+}}/showHighlightedRanges.cpp"]
+// CHECK-SAME: }
+// CHECK-SAME: {"name":"_Z4testv","count":1,"regions":[
+// CHECK-SAME: {{(\[[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+\],?)+}}
+// CHECK-SAME: ],
+// CHECK-SAME: "filenames":["{{[^\"]+}}/showHighlightedRanges.cpp"]
+// CHECK-SAME: }
+// CHECK-SAME: {"name":"main","count":1,"regions":[
+// CHECK-SAME: {{(\[[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+\],?)+}}
+// CHECK-SAME: ],
+// CHECK-SAME: "filenames":["{{[^\"]+}}/showHighlightedRanges.cpp"]
+// CHECK-SAME: }],
+
+
+// Full Export Summary
+// CHECK-SAME: "totals":{
+// CHECK-SAME: "lines":{"count":40,"covered":26,"percent":65,"noncode":0},
+// CHECK-SAME: "functions":{"count":4,"covered":4,"percent":100},
+// CHECK-SAME: "regions":{"count":19,"covered":11,"notcovered":8,"percent":57}}
+
+// Close the export object, data array, and root object
+// CHECK-SAME: }]}
Index: llvm/trunk/test/tools/llvm-cov/Inputs/lineExecutionCounts.json
===================================================================
--- llvm/trunk/test/tools/llvm-cov/Inputs/lineExecutionCounts.json
+++ llvm/trunk/test/tools/llvm-cov/Inputs/lineExecutionCounts.json
@@ -0,0 +1,38 @@
+// Metadata section
+// CHECK: {"version":"1.0.0","type":"llvm.coverage.json.export","data":[
+
+// Open Export
+// CHECK-SAME: {"object":"{{[^\"]+}}","files":[
+
+// File Object
+// CHECK-SAME: {"filename":"{{[^\"]+}}/showLineExecutionCounts.cpp",
+// CHECK-SAME: "segments":[
+// CHECK-SAME: {{(\[[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+\],?)+}}],
+// CHECK-SAME: "expansions":[],
+
+// Verify the Summary Section for the first file
+// CHECK-SAME: "summary":{
+// CHECK-SAME: "lines":{"count":20,"covered":16,"percent":80,"noncode":0},
+// CHECK-SAME: "functions":{"count":1,"covered":1,"percent":100},
+// CHECK-SAME: "regions":{"count":10,"covered":7,"notcovered":3,"percent":70}}}
+
+// Close Files Array
+// CHECK-SAME: ],
+
+// Functions List
+// CHECK-SAME: "functions":[
+// CHECK-SAME: {"name":"main","count":161,"regions":[
+// CHECK-SAME: {{(\[[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+\],?)+}}
+// CHECK-SAME: ],
+// CHECK-SAME: "filenames":["{{[^\"]+}}/showLineExecutionCounts.cpp"]
+// CHECK-SAME: }],
+
+
+// Full Export Summary
+// CHECK-SAME: "totals":{
+// CHECK-SAME: "lines":{"count":20,"covered":16,"percent":80,"noncode":0},
+// CHECK-SAME: "functions":{"count":1,"covered":1,"percent":100},
+// CHECK-SAME: "regions":{"count":10,"covered":7,"notcovered":3,"percent":70}}
+
+// Close the export object, data array, and root object
+// CHECK-SAME: }]}
Index: llvm/trunk/test/tools/llvm-cov/Inputs/regionMarkers.json
===================================================================
--- llvm/trunk/test/tools/llvm-cov/Inputs/regionMarkers.json
+++ llvm/trunk/test/tools/llvm-cov/Inputs/regionMarkers.json
@@ -0,0 +1,37 @@
+// Metadata section
+// CHECK: {"version":"1.0.0","type":"llvm.coverage.json.export","data":[
+
+// Open Export
+// CHECK-SAME: {"object":"{{[^\"]+}}","files":[
+
+// File Object
+// CHECK-SAME: {"filename":"{{[^\"]+}}/showRegionMarkers.cpp",
+// CHECK-SAME: "segments":[
+// CHECK-SAME: {{(\[[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+\],?)+}}],
+// CHECK-SAME: "expansions":[],
+
+// Verify the Summary Section for the first file
+// CHECK-SAME: "summary":{
+// CHECK-SAME: "lines":{"count":21,"covered":17,"percent":80,"noncode":0},
+// CHECK-SAME: "functions":{"count":1,"covered":1,"percent":100},
+// CHECK-SAME: "regions":{"count":10,"covered":7,"notcovered":3,"percent":70}}
+
+// Close Files Array
+// CHECK-SAME: ],
+
+// Functions List
+// CHECK-SAME: "functions":[
+// CHECK-SAME: {"name":"main","count":1111000,"regions":[
+// CHECK-SAME: {{(\[[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+\],?)+}}
+// CHECK-SAME: ],
+// CHECK-SAME: "filenames":["{{[^\"]+}}/showRegionMarkers.cpp"]
+// CHECK-SAME: }],
+
+// Full Export Summary
+// CHECK-SAME: "totals":{
+// CHECK-SAME: "lines":{"count":21,"covered":17,"percent":80,"noncode":0},
+// CHECK-SAME: "functions":{"count":1,"covered":1,"percent":100},
+// CHECK-SAME: "regions":{"count":10,"covered":7,"notcovered":3,"percent":70}}
+
+// Close the export object, data array, and root object
+// CHECK-SAME: }]}
Index: llvm/trunk/test/tools/llvm-cov/Inputs/showExpansions.json
===================================================================
--- llvm/trunk/test/tools/llvm-cov/Inputs/showExpansions.json
+++ llvm/trunk/test/tools/llvm-cov/Inputs/showExpansions.json
@@ -0,0 +1,51 @@
+// Metadata section
+// CHECK: {"version":"1.0.0","type":"llvm.coverage.json.export","data":[
+
+// Open Export
+// CHECK-SAME: {"object":"{{[^\"]+}}","files":[
+
+// File Object
+// CHECK-SAME: {"filename":"{{[^\"]+}}/showExpansions.cpp",
+// CHECK-SAME: "segments":[
+// CHECK-SAME: {{(\[[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+\],?)+}}],
+// CHECK-SAME: "expansions":[
+// CHECK-SAME: {"source_region":[24,5,24,17,100,0,1,1],
+// CHECK-SAME: "target_regions":[
+// CHECK-SAME: {{(\[[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+\],?)+}}
+// CHECK-SAME: ],
+
+// Yes, 4 of the same filename in a row
+// CHECK-SAME: "filenames":[
+// CHECK-SAME: "{{[^\"]+}}/showExpansions.cpp","{{[^\"]+}}/showExpansions.cpp",
+// CHECK-SAME: "{{[^\"]+}}/showExpansions.cpp","{{[^\"]+}}/showExpansions.cpp"]
+// CHECK-SAME: }],
+
+// Verify the Summary Section for the first file
+// CHECK-SAME: "summary":{
+// CHECK-SAME: "lines":{"count":17,"covered":15,"percent":88,"noncode":0},
+// CHECK-SAME: "functions":{"count":1,"covered":1,"percent":100},
+// CHECK-SAME: "regions":{"count":13,"covered":12,"notcovered":1,"percent":92}}
+
+// Close Files Array
+// CHECK-SAME: ],
+
+// Functions List
+// CHECK-SAME: "functions":[
+// CHECK-SAME: {"name":"main","count":1,"regions":[
+// CHECK-SAME: {{(\[[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+\],?)+}}
+// CHECK-SAME: ],
+// CHECK-SAME: "filenames":[
+// CHECK-SAME: "{{[^\"]+}}/showExpansions.cpp",
+// CHECK-SAME: "{{[^\"]+}}/showExpansions.cpp",
+// CHECK-SAME: "{{[^\"]+}}/showExpansions.cpp",
+// CHECK-SAME: "{{[^\"]+}}/showExpansions.cpp"]
+// CHECK-SAME: }],
+
+// Full Export Summary
+// CHECK-SAME: "totals":{
+// CHECK-SAME: "lines":{"count":17,"covered":15,"percent":88,"noncode":0},
+// CHECK-SAME: "functions":{"count":1,"covered":1,"percent":100},
+// CHECK-SAME: "regions":{"count":13,"covered":12,"notcovered":1,"percent":92}}
+
+// Close the export object, data array, and root object
+// CHECK-SAME: }]}
Index: llvm/trunk/test/tools/llvm-cov/Inputs/universal-binary.json
===================================================================
--- llvm/trunk/test/tools/llvm-cov/Inputs/universal-binary.json
+++ llvm/trunk/test/tools/llvm-cov/Inputs/universal-binary.json
@@ -0,0 +1,36 @@
+// Metadata section
+// CHECK: {"version":"1.0.0","type":"llvm.coverage.json.export","data":[
+
+// Open Export
+// CHECK-SAME: {"object":"{{[^\"]+}}","files":[
+
+// File Object
+// CHECK-SAME: {"filename":"{{[^\"]+}}/universal-binary.c",
+// CHECK-SAME: "segments":[
+// CHECK-SAME: {{(\[[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+\],?)+}}],
+// CHECK-SAME: "expansions":[],
+
+// Verify the Summary Section for the first file
+// CHECK-SAME: "summary":{
+// CHECK-SAME: "lines":{"count":1,"covered":1,"percent":100,"noncode":0},
+// CHECK-SAME: "functions":{"count":1,"covered":1,"percent":100},
+// CHECK-SAME: "regions":{"count":1,"covered":1,"notcovered":0,"percent":100}}
+
+// Close Files Array
+// CHECK-SAME: ],
+
+// Functions List
+// CHECK-SAME: "functions":[
+// CHECK-SAME: {"name":"main","count":100,"regions":[
+// CHECK-SAME: {{(\[[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+,[0-9]+\],?)+}}],
+// CHECK-SAME: "filenames":["{{[^\"]+}}/universal-binary.c"]
+// CHECK-SAME: }],
+
+// Full Export Summary
+// CHECK-SAME: "totals":{
+// CHECK-SAME: "lines":{"count":1,"covered":1,"percent":100,"noncode":0},
+// CHECK-SAME: "functions":{"count":1,"covered":1,"percent":100},
+// CHECK-SAME: "regions":{"count":1,"covered":1,"notcovered":0,"percent":100}
+
+// Close the export object, data array, and root object
+// CHECK-SAME: }]}
Index: llvm/trunk/test/tools/llvm-cov/binary-formats.c
===================================================================
--- llvm/trunk/test/tools/llvm-cov/binary-formats.c
+++ llvm/trunk/test/tools/llvm-cov/binary-formats.c
@@ -7,3 +7,7 @@
 // RUN: llvm-cov show %S/Inputs/binary-formats.macho32l -instr-profile %t.profdata -filename-equivalence %s | FileCheck %s
 // RUN: llvm-cov show %S/Inputs/binary-formats.macho64l -instr-profile %t.profdata -filename-equivalence %s | FileCheck %s
 // RUN: llvm-cov show %S/Inputs/binary-formats.macho32b -instr-profile %t.profdata -filename-equivalence %s | FileCheck %s
+
+// RUN: llvm-cov export %S/Inputs/binary-formats.macho32l -instr-profile %t.profdata | FileCheck %S/Inputs/binary-formats.canonical.json
+// RUN: llvm-cov export %S/Inputs/binary-formats.macho64l -instr-profile %t.profdata | FileCheck %S/Inputs/binary-formats.canonical.json
+// RUN: llvm-cov export %S/Inputs/binary-formats.macho32b -instr-profile %t.profdata | FileCheck %S/Inputs/binary-formats.canonical.json
Index: llvm/trunk/test/tools/llvm-cov/showExpansions.cpp
===================================================================
--- llvm/trunk/test/tools/llvm-cov/showExpansions.cpp
+++ llvm/trunk/test/tools/llvm-cov/showExpansions.cpp
@@ -24,3 +24,4 @@
     DO_SOMETHING(i); // CHECK-DAG: Expansion at line [[@LINE]], 5 -> 17
   return 0;
 }
+// RUN: llvm-cov export %S/Inputs/showExpansions.covmapping -instr-profile %S/Inputs/showExpansions.profdata 2>&1 | FileCheck %S/Inputs/showExpansions.json
Index: llvm/trunk/test/tools/llvm-cov/showHighlightedRanges.cpp
===================================================================
--- llvm/trunk/test/tools/llvm-cov/showHighlightedRanges.cpp
+++ llvm/trunk/test/tools/llvm-cov/showHighlightedRanges.cpp
@@ -43,3 +43,4 @@
   func2(9);
   return 0;
 }
+// RUN: llvm-cov export %S/Inputs/highlightedRanges.covmapping -instr-profile %S/Inputs/highlightedRanges.profdata 2>&1 | FileCheck %S/Inputs/highlightedRanges.json
Index: llvm/trunk/test/tools/llvm-cov/showLineExecutionCounts.cpp
===================================================================
--- llvm/trunk/test/tools/llvm-cov/showLineExecutionCounts.cpp
+++ llvm/trunk/test/tools/llvm-cov/showLineExecutionCounts.cpp
@@ -69,3 +69,7 @@
 // HTML: <td class='covered-line'><pre>161</pre></td><td class='line-number'><a name='L[[@LINE-44]]'><pre>[[@LINE-44]]</pre></a></td><td class='code'><pre>}
 // HTML-WHOLE-FILE: <td class='uncovered-line'></td><td class='line-number'><a name='L[[@LINE-44]]'><pre>[[@LINE-44]]</pre></a></td><td class='code'><pre>// after
 // HTML-FILTER-NOT: <td class='uncovered-line'></td><td class='line-number'><a name='L[[@LINE-45]]'><pre>[[@LINE-45]]</pre></a></td><td class='code'><pre>// after
+
+// RUN: llvm-cov export %S/Inputs/lineExecutionCounts.covmapping -instr-profile %t.profdata -name=main 2>/dev/null > %t.json
+// FileCheck -input-file=%t.json %S/Inputs/lineExecutionCounts.json
+// RUN: cat %t.json | %python -c 'import json, sys; json.loads(sys.stdin.read())'
Index: llvm/trunk/test/tools/llvm-cov/showRegionMarkers.cpp
===================================================================
--- llvm/trunk/test/tools/llvm-cov/showRegionMarkers.cpp
+++ llvm/trunk/test/tools/llvm-cov/showRegionMarkers.cpp
@@ -23,3 +23,5 @@
 }
 
 // RUN: llvm-cov show %S/Inputs/regionMarkers.covmapping -instr-profile %t.profdata -show-regions -dump -filename-equivalence %s 2>&1 | FileCheck %s
+
+// RUN: llvm-cov export %S/Inputs/regionMarkers.covmapping -instr-profile %t.profdata 2>&1 | FileCheck %S/Inputs/regionMarkers.json
Index: llvm/trunk/test/tools/llvm-cov/universal-binary.c
===================================================================
--- llvm/trunk/test/tools/llvm-cov/universal-binary.c
+++ llvm/trunk/test/tools/llvm-cov/universal-binary.c
@@ -5,6 +5,8 @@
 
 // RUN: llvm-profdata merge %S/Inputs/universal-binary.proftext -o %t.profdata
 // RUN: llvm-cov show %S/Inputs/universal-binary -instr-profile %t.profdata -filename-equivalence %s -arch x86_64 | FileCheck %s
+// RUN: llvm-cov export %S/Inputs/universal-binary -instr-profile %t.profdata -arch x86_64 2>&1 | FileCheck %S/Inputs/universal-binary.json
+
 
 // RUN: not llvm-cov show %S/Inputs/universal-binary -instr-profile %t.profdata -filename-equivalence %s -arch i386 2>&1 | FileCheck --check-prefix=WRONG-ARCH %s
 // WRONG-ARCH: Failed to load coverage
Index: llvm/trunk/tools/llvm-cov/CMakeLists.txt
===================================================================
--- llvm/trunk/tools/llvm-cov/CMakeLists.txt
+++ llvm/trunk/tools/llvm-cov/CMakeLists.txt
@@ -4,6 +4,7 @@
   llvm-cov.cpp
   gcov.cpp
   CodeCoverage.cpp
+  CoverageExporterJson.cpp
   CoverageFilters.cpp
   CoverageReport.cpp
   CoverageSummaryInfo.cpp
Index: llvm/trunk/tools/llvm-cov/CodeCoverage.cpp
===================================================================
--- llvm/trunk/tools/llvm-cov/CodeCoverage.cpp
+++ llvm/trunk/tools/llvm-cov/CodeCoverage.cpp
@@ -38,6 +38,10 @@
 using namespace llvm;
 using namespace coverage;
 
+void exportCoverageDataToJson(StringRef ObjectFilename,
+                              const coverage::CoverageMapping &CoverageMapping,
+                              raw_ostream &OS);
+
 namespace {
 /// \brief The implementation of the coverage tool.
 class CodeCoverageTool {
@@ -46,7 +50,9 @@
     /// \brief The show command.
     Show,
     /// \brief The report command.
-    Report
+    Report,
+    /// \brief The export command.
+    Export
   };
 
   /// \brief Print the error message to the error output stream.
@@ -94,6 +100,9 @@
   int report(int argc, const char **argv,
              CommandLineParserType commandLineParser);
 
+  int export_(int argc, const char **argv,
+              CommandLineParserType commandLineParser);
+
   std::string ObjectFilename;
   CoverageViewOptions ViewOpts;
   std::string PGOFilename;
@@ -534,6 +543,8 @@
     return show(argc, argv, commandLineParser);
   case Report:
     return report(argc, argv, commandLineParser);
+  case Export:
+    return export_(argc, argv, commandLineParser);
   }
   return 0;
 }
@@ -694,6 +705,24 @@
   return 0;
 }
 
+int CodeCoverageTool::export_(int argc, const char **argv,
+                              CommandLineParserType commandLineParser) {
+
+  auto Err = commandLineParser(argc, argv);
+  if (Err)
+    return Err;
+
+  auto Coverage = load();
+  if (!Coverage) {
+    error("Could not load coverage information");
+    return 1;
+  }
+
+  exportCoverageDataToJson(ObjectFilename, *Coverage.get(), outs());
+
+  return 0;
+}
+
 int showMain(int argc, const char *argv[]) {
   CodeCoverageTool Tool;
   return Tool.run(CodeCoverageTool::Show, argc, argv);
@@ -703,3 +732,8 @@
   CodeCoverageTool Tool;
   return Tool.run(CodeCoverageTool::Report, argc, argv);
 }
+
+int exportMain(int argc, const char *argv[]) {
+  CodeCoverageTool Tool;
+  return Tool.run(CodeCoverageTool::Export, argc, argv);
+}
Index: llvm/trunk/tools/llvm-cov/CoverageExporterJson.cpp
===================================================================
--- llvm/trunk/tools/llvm-cov/CoverageExporterJson.cpp
+++ llvm/trunk/tools/llvm-cov/CoverageExporterJson.cpp
@@ -0,0 +1,418 @@
+//===- CoverageExporterJson.cpp - Code coverage export --------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements export of code coverage data to JSON.
+//
+//===----------------------------------------------------------------------===//
+
+//===----------------------------------------------------------------------===//
+//
+// The json code coverage export follows the following format
+// Root: dict => Root Element containing metadata
+// -- Data: array => Homogeneous array of one or more export objects
+// ---- Export: dict => Json representation of one CoverageMapping
+// ------ Files: array => List of objects describing coverage for files
+// -------- File: dict => Coverage for a single file
+// ---------- Segments: array => List of Segments contained in the file
+// ------------ Segment: dict => Describes a segment of the file with a counter
+// ---------- Expansions: array => List of expansion records
+// ------------ Expansion: dict => Object that descibes a single expansion
+// -------------- CountedRegion: dict => The region to be expanded
+// -------------- TargetRegions: array => List of Regions in the expansion
+// ---------------- CountedRegion: dict => Single Region in the expansion
+// ---------- Summary: dict => Object summarizing the coverage for this file
+// ------------ LineCoverage: dict => Object summarizing line coverage
+// ------------ FunctionCoverage: dict => Object summarizing function coverage
+// ------------ RegionCoverage: dict => Object summarizing region coverage
+// ------ Functions: array => List of objects describing coverage for functions
+// -------- Function: dict => Coverage info for a single function
+// ---------- Filenames: array => List of filenames that the function relates to
+// ---- Summary: dict => Object summarizing the coverage for the entire binary
+// ------ LineCoverage: dict => Object summarizing line coverage
+// ------ FunctionCoverage: dict => Object summarizing function coverage
+// ------ RegionCoverage: dict => Object summarizing region coverage
+//
+//===----------------------------------------------------------------------===//
+
+#include "CoverageSummaryInfo.h"
+#include "CoverageViewOptions.h"
+#include "llvm/ProfileData/Coverage/CoverageMapping.h"
+#include <stack>
+
+/// \brief Major version of the JSON Coverage Export Format.
+#define LLVM_COVERAGE_EXPORT_JSON_MAJOR 1
+
+/// \brief Minor version of the JSON Coverage Export Format.
+#define LLVM_COVERAGE_EXPORT_JSON_MINOR 0
+
+/// \brief Patch version of the JSON Coverage Export Format.
+#define LLVM_COVERAGE_EXPORT_JSON_PATCH 0
+
+/// \brief The semantic version combined as a string.
+#define LLVM_COVERAGE_EXPORT_JSON_STR "1.0.0"
+
+/// \brief Unique type identifier for JSON coverage export.
+#define LLVM_COVERAGE_EXPORT_JSON_TYPE_STR "llvm.coverage.json.export"
+
+using namespace llvm;
+using namespace coverage;
+
+class CoverageExporterJson {
+  /// \brief A Name of the object file coverage is for.
+  StringRef ObjectFilename;
+
+  /// \brief Output stream to print JSON to.
+  raw_ostream &OS;
+
+  /// \brief The full CoverageMapping object to export.
+  CoverageMapping Coverage;
+
+  /// \brief States that the JSON rendering machine can be in.
+  enum JsonState { None, NonEmptyElement, EmptyElement };
+
+  /// \brief Tracks state of the JSON output.
+  std::stack<JsonState> State;
+
+  /// \brief Get the object filename.
+  StringRef getObjectFilename() const { return ObjectFilename; }
+
+  /// \brief Emit a serialized scalar.
+  void emitSerialized(const int64_t Value) { OS << Value; }
+
+  /// \brief Emit a serialized string.
+  void emitSerialized(const std::string &Value) { OS << "\"" << Value << "\""; }
+
+  /// \brief Emit a comma if there is a previous element to delimit.
+  void emitComma() {
+    if (State.top() == JsonState::NonEmptyElement) {
+      OS << ",";
+    } else if (State.top() == JsonState::EmptyElement) {
+      State.pop();
+      assert((State.size() >= 1) && "Closed too many JSON elements");
+      State.push(JsonState::NonEmptyElement);
+    }
+  }
+
+  /// \brief Emit a starting dictionary/object character.
+  void emitDictStart() {
+    emitComma();
+    State.push(JsonState::EmptyElement);
+    OS << "{";
+  }
+
+  /// \brief Emit a dictionary/object key but no value.
+  void emitDictKey(const std::string &Key) {
+    emitComma();
+    OS << "\"" << Key << "\":";
+    State.pop();
+    assert((State.size() >= 1) && "Closed too many JSON elements");
+
+    // We do not want to emit a comma after this key.
+    State.push(JsonState::EmptyElement);
+  }
+
+  /// \brief Emit a dictionary/object key/value pair.
+  template <typename V>
+  void emitDictElement(const std::string &Key, const V &Value) {
+    emitComma();
+    emitSerialized(Key);
+    OS << ":";
+    emitSerialized(Value);
+  }
+
+  /// \brief Emit a closing dictionary/object character.
+  void emitDictEnd() {
+    State.pop();
+    assert((State.size() >= 1) && "Closed too many JSON elements");
+    OS << "}";
+  }
+
+  /// \brief Emit a starting array character.
+  void emitArrayStart() {
+    emitComma();
+    State.push(JsonState::EmptyElement);
+    OS << "[";
+  }
+
+  /// \brief Emit an array element.
+  template <typename V> void emitArrayElement(const V &Value) {
+    emitComma();
+    emitSerialized(Value);
+  }
+
+  /// \brief emit a closing array character.
+  void emitArrayEnd() {
+    State.pop();
+    assert((State.size() >= 1) && "Closed too many JSON elements");
+    OS << "]";
+  }
+
+  /// \brief Render the CoverageMapping object.
+  void renderRoot() {
+    // Start Root of JSON object.
+    emitDictStart();
+
+    emitDictElement("version", LLVM_COVERAGE_EXPORT_JSON_STR);
+    emitDictElement("type", LLVM_COVERAGE_EXPORT_JSON_TYPE_STR);
+    emitDictKey("data");
+
+    // Start List of Exports.
+    emitArrayStart();
+
+    // Start Export.
+    emitDictStart();
+    emitDictElement("object", getObjectFilename());
+
+    emitDictKey("files");
+    FileCoverageSummary Totals = FileCoverageSummary("Totals");
+    renderFiles(Coverage.getUniqueSourceFiles(), Totals);
+
+    emitDictKey("functions");
+    renderFunctions(Coverage.getCoveredFunctions());
+
+    emitDictKey("totals");
+    renderSummary(Totals);
+
+    // End Export.
+    emitDictEnd();
+
+    // End List of Exports.
+    emitArrayEnd();
+
+    // End Root of JSON Object.
+    emitDictEnd();
+
+    assert((State.top() == JsonState::None) &&
+           "All Elements In JSON were Closed");
+  }
+
+  /// \brief Render an array of all the given functions.
+  void
+  renderFunctions(const iterator_range<FunctionRecordIterator> &Functions) {
+    // Start List of Functions.
+    emitArrayStart();
+
+    for (const auto &Function : Functions) {
+      // Start Function.
+      emitDictStart();
+
+      emitDictElement("name", Function.Name);
+      emitDictElement("count", Function.ExecutionCount);
+      emitDictKey("regions");
+
+      renderRegions(Function.CountedRegions);
+
+      emitDictKey("filenames");
+
+      // Start Filenames for Function.
+      emitArrayStart();
+
+      for (const auto &FileName : Function.Filenames)
+        emitArrayElement(FileName);
+
+      // End Filenames for Function.
+      emitArrayEnd();
+
+      // End Function.
+      emitDictEnd();
+    }
+
+    // End List of Functions.
+    emitArrayEnd();
+  }
+
+  /// \brief Render an array of all the source files, also pass back a Summary.
+  void renderFiles(ArrayRef<StringRef> SourceFiles,
+                   FileCoverageSummary &Summary) {
+    // Start List of Files.
+    emitArrayStart();
+    for (const auto &SourceFile : SourceFiles) {
+      // Render the file.
+      auto FileCoverage = Coverage.getCoverageForFile(SourceFile);
+      renderFile(FileCoverage);
+
+      for (const auto &F : Coverage.getCoveredFunctions(SourceFile))
+        Summary.addFunction(FunctionCoverageSummary::get(F));
+    }
+
+    // End List of Files.
+    emitArrayEnd();
+  }
+
+  /// \brief Render a single file.
+  void renderFile(const CoverageData &FileCoverage) {
+    // Start File.
+    emitDictStart();
+
+    emitDictElement("filename", FileCoverage.getFilename());
+    emitDictKey("segments");
+
+    // Start List of Segments.
+    emitArrayStart();
+
+    for (const auto &Segment : FileCoverage)
+      renderSegment(Segment);
+
+    // End List of Segments.
+    emitArrayEnd();
+
+    emitDictKey("expansions");
+
+    // Start List of Expansions.
+    emitArrayStart();
+
+    for (const auto &Expansion : FileCoverage.getExpansions())
+      renderExpansion(Expansion);
+
+    // End List of Expansions.
+    emitArrayEnd();
+
+    FileCoverageSummary Summary =
+        FileCoverageSummary(FileCoverage.getFilename());
+    for (const auto &F :
+         Coverage.getCoveredFunctions(FileCoverage.getFilename()))
+      Summary.addFunction(FunctionCoverageSummary::get(F));
+
+    emitDictKey("summary");
+    renderSummary(Summary);
+
+    // End File.
+    emitDictEnd();
+  }
+
+  /// \brief Render a CoverageSegment.
+  void renderSegment(const CoverageSegment &Segment) {
+    // Start Segment.
+    emitArrayStart();
+
+    emitArrayElement(Segment.Line);
+    emitArrayElement(Segment.Col);
+    emitArrayElement(Segment.Count);
+    emitArrayElement(Segment.HasCount);
+    emitArrayElement(Segment.IsRegionEntry);
+
+    // End Segment.
+    emitArrayEnd();
+  }
+
+  /// \brief Render an ExpansionRecord.
+  void renderExpansion(const ExpansionRecord &Expansion) {
+    // Start Expansion.
+    emitDictStart();
+
+    // Mark the beginning and end of this expansion in the source file.
+    emitDictKey("source_region");
+    renderRegion(Expansion.Region);
+
+    // Enumerate the coverage information for the expansion.
+    emitDictKey("target_regions");
+    renderRegions(Expansion.Function.CountedRegions);
+
+    emitDictKey("filenames");
+    // Start List of Filenames to map the fileIDs.
+    emitArrayStart();
+    for (const auto &Filename : Expansion.Function.Filenames)
+      emitArrayElement(Filename);
+    // End List of Filenames.
+    emitArrayEnd();
+
+    // End Expansion.
+    emitDictEnd();
+  }
+
+  /// \brief Render a list of CountedRegions.
+  void renderRegions(ArrayRef<CountedRegion> Regions) {
+    // Start List of Regions.
+    emitArrayStart();
+
+    for (const auto &Region : Regions)
+      renderRegion(Region);
+
+    // End List of Regions.
+    emitArrayEnd();
+  }
+
+  /// \brief Render a single CountedRegion.
+  void renderRegion(const CountedRegion &Region) {
+    // Start CountedRegion.
+    emitArrayStart();
+
+    emitArrayElement(Region.LineStart);
+    emitArrayElement(Region.ColumnStart);
+    emitArrayElement(Region.LineEnd);
+    emitArrayElement(Region.ColumnEnd);
+    emitArrayElement(Region.ExecutionCount);
+    emitArrayElement(Region.FileID);
+    emitArrayElement(Region.ExpandedFileID);
+    emitArrayElement(Region.Kind);
+
+    // End CountedRegion.
+    emitArrayEnd();
+  }
+
+  /// \brief Render a FileCoverageSummary.
+  void renderSummary(const FileCoverageSummary &Summary) {
+    // Start Summary for the file.
+    emitDictStart();
+
+    emitDictKey("lines");
+
+    // Start Line Coverage Summary.
+    emitDictStart();
+    emitDictElement("count", Summary.LineCoverage.NumLines);
+    emitDictElement("covered", Summary.LineCoverage.Covered);
+    emitDictElement("percent", Summary.LineCoverage.getPercentCovered());
+    emitDictElement("noncode", Summary.LineCoverage.NonCodeLines);
+    // End Line Coverage Summary.
+    emitDictEnd();
+
+    emitDictKey("functions");
+
+    // Start Function Coverage Summary.
+    emitDictStart();
+    emitDictElement("count", Summary.FunctionCoverage.NumFunctions);
+    emitDictElement("covered", Summary.FunctionCoverage.Executed);
+    emitDictElement("percent", Summary.FunctionCoverage.getPercentCovered());
+    // End Function Coverage Summary.
+    emitDictEnd();
+
+    emitDictKey("regions");
+
+    // Start Region Coverage Summary.
+    emitDictStart();
+    emitDictElement("count", Summary.RegionCoverage.NumRegions);
+    emitDictElement("covered", Summary.RegionCoverage.Covered);
+    emitDictElement("notcovered", Summary.RegionCoverage.NotCovered);
+    emitDictElement("percent", Summary.RegionCoverage.getPercentCovered());
+    // End Region Coverage Summary.
+    emitDictEnd();
+
+    // End Summary for the file.
+    emitDictEnd();
+  }
+
+public:
+  CoverageExporterJson(StringRef ObjectFilename,
+                       const CoverageMapping &CoverageMapping, raw_ostream &OS)
+      : ObjectFilename(ObjectFilename), OS(OS), Coverage(CoverageMapping) {
+    State.push(JsonState::None);
+  }
+
+  /// \brief Print the CoverageMapping.
+  void print() { renderRoot(); }
+};
+
+/// \brief Export the given CoverageMapping to a JSON Format.
+void exportCoverageDataToJson(StringRef ObjectFilename,
+                              const CoverageMapping &CoverageMapping,
+                              raw_ostream &OS) {
+  auto Exporter = CoverageExporterJson(ObjectFilename, CoverageMapping, OS);
+
+  Exporter.print();
+}
Index: llvm/trunk/tools/llvm-cov/llvm-cov.cpp
===================================================================
--- llvm/trunk/tools/llvm-cov/llvm-cov.cpp
+++ llvm/trunk/tools/llvm-cov/llvm-cov.cpp
@@ -30,6 +30,9 @@
 /// \brief The main entry point for the 'report' subcommand.
 int reportMain(int argc, const char *argv[]);
 
+/// \brief The main entry point for the 'export' subcommand.
+int exportMain(int argc, const char *argv[]);
+
 /// \brief The main entry point for the 'convert-for-testing' subcommand.
 int convertForTestingMain(int argc, const char *argv[]);
 
@@ -38,12 +41,14 @@
 
 /// \brief Top level help.
 static int helpMain(int argc, const char *argv[]) {
-  errs() << "Usage: llvm-cov {gcov|report|show} [OPTION]...\n\n"
+  errs() << "Usage: llvm-cov {export|gcov|report|show} [OPTION]...\n\n"
          << "Shows code coverage information.\n\n"
          << "Subcommands:\n"
+         << "  export: Export instrprof file to structured format.\n"
          << "  gcov:   Work with the gcov format.\n"
-         << "  show:   Annotate source files using instrprof style coverage.\n"
-         << "  report: Summarize instrprof style coverage information.\n";
+         << "  report: Summarize instrprof style coverage information.\n"
+         << "  show:   Annotate source files using instrprof style coverage.\n";
+
   return 0;
 }
 
@@ -68,6 +73,7 @@
     typedef int (*MainFunction)(int, const char *[]);
     MainFunction Func = StringSwitch<MainFunction>(argv[1])
                             .Case("convert-for-testing", convertForTestingMain)
+                            .Case("export", exportMain)
                             .Case("gcov", gcovMain)
                             .Case("report", reportMain)
                             .Case("show", showMain)