[clang-offload-bundler] Add option -allow-missing-bundles

[yaxunl]

Summary

There are out-of-tree tools using clang-offload-bundler to extract
bundles from bundled files. When a bundle is not in the bundled
file, clang-offload-bundler is expected to emit an error message
and return non-zero value. However currently clang-offload-bundler
silently generates empty file for the missing bundles.

Since OpenMP/HIP toolchains expect the current behavior, an option
-allow-missing-bundles is added to let clang-offload-bundler
create empty file when a bundle is missing when unbundling.
The unbundling job action is updated to use this option by
default.

clang-offload-bundler itself will emit error when a bundle
is missing when unbundling by default.

Changes are also made to check duplicate targets in -targets
option and emit error.

[tra]

clang/tools/clang-offload-bundler/ClangOffloadBundler.cpp

980

Do we need to report complete list of missing bundles?
Can we just report the first one we've encountered and abort the command?

985

This assumes that all items on the WorkList were unique.
If some of the WorkList items were duplicated, then there will be fewer items in Sorted and the I == Last comparison will never be true.
I'd use Sorted.size() instead.

998–999

Can we, instead use an explicit option to enable this 'make empty files for missing targets' and report missing targets as an error otherwise?
I would assume that missing a target explicitly specified on command line would be an error more often than not. After all we've asked to extract something which implies that that 'something' exists. I.e. if I tell unzip to unpack a non-existing file from an archive, I do not expect it to give me an empty file.

[yaxunl]

clang/tools/clang-offload-bundler/ClangOffloadBundler.cpp

980

Better to report all missing bundles since the info is available here and useful.

985

clang-offload-bundler does not allow duplicated targets. It asserts when duplicated targets in options are found when unbundling. Will add check for duplicate targets in options and emit error.

998–999

will do

[yaxunl]

Revised by Artem's comments.

[tra]

LGTM.

The patch could use an OK with OMP folks, considering that we've changed the way offload bunder is invoked for OMP.

clang/tools/clang-offload-bundler/ClangOffloadBundler.cpp

985

I'd still use Sorted.size() as it's the Sorted you're iterating on.

1126

Nit: .contains(Target) ?

[yaxunl]

@ABataev Is this patch OK for OpenMP? It is NFC for OpenMP toolchain but affects using clang-offload-bundler as a standalone tool. Thanks.

clang/tools/clang-offload-bundler/ClangOffloadBundler.cpp

985

will fix

1126

will fix

[ABataev]

In D93068#2457946, @yaxunl wrote:

@ABataev Is this patch OK for OpenMP? It is NFC for OpenMP toolchain but affects using clang-offload-bundler as a standalone tool. Thanks.

Yes, I think it is ok.

clang/lib/Driver/ToolChains/Clang.cpp

void OffloadBundler::ConstructJobMultipleOutputs(
   UB += "-outputs=";
   for (unsigned I = 0; I < Outputs.size(); ++I) {
     if (I)
       UB += ',';
     UB += DepInfo[I].DependentToolChain->getInputFilename(Outputs[I]);
   }
   CmdArgs.push_back(TCArgs.MakeArgString(UB));
   CmdArgs.push_back("-unbundle");
+  CmdArgs.push_back("-allow-missing-bundles");
 
   // All the inputs are encoded as commands.
   C.addCommand(std::make_unique<Command>(
       JA, *this, ResponseFileSupport::None(),
       TCArgs.MakeArgString(getToolChain().GetProgramPath(getShortName())),
       CmdArgs, None, Outputs));
 }
 

clang/test/Driver/clang-offload-bundler.c

 // Check help message.
 //
 // RUN: clang-offload-bundler --help | FileCheck %s --check-prefix CK-HELP
 // CK-HELP: {{.*}}OVERVIEW: A tool to bundle several input files of the specified type <type>
 // CK-HELP: {{.*}}referring to the same source file but different targets into a single
 // CK-HELP: {{.*}}one. The resulting file can also be unbundled into different files by
 // CK-HELP: {{.*}}this tool if -unbundle is provided.
 // CK-HELP: {{.*}}USAGE: clang-offload-bundler [options]
+// CK-HELP: {{.*}}-allow-missing-bundles {{.*}}- Create empty files if bundles are missing when unbundling
 // CK-HELP: {{.*}}-inputs=<string>  - [<input file>,...]
 // CK-HELP: {{.*}}-list {{.*}}- List bundle IDs in the bundled file.
 // CK-HELP: {{.*}}-outputs=<string> - [<output file>,...]
 // CK-HELP: {{.*}}-targets=<string> - [<offload kind>-<target triple>,...]
 // CK-HELP: {{.*}}-type=<string>    - Type of the files to be bundled/unbundled.
 // CK-HELP: {{.*}}Current supported types are:
 // CK-HELP: {{.*}}i {{.*}}- cpp-output
 // CK-HELP: {{.*}}ii {{.*}}- c++-cpp-output

 // RUN: not clang-offload-bundler -type=i -targets=hxst-powerpcxxle-ibm-linux-gnu,openxp-pxxerpc64le-ibm-linux-gnu,xpenmp-x86_xx-pc-linux-gnu -inputs=%t.i,%t.tgt1,%t.tgt2 -outputs=%t.bundle.i 2>&1 | FileCheck %s --check-prefix CK-ERR8
 // CK-ERR8: error: invalid target 'hxst-powerpcxxle-ibm-linux-gnu', unknown offloading kind 'hxst', unknown target triple 'powerpcxxle-ibm-linux-gnu'
 // CK-ERR8: error: invalid target 'openxp-pxxerpc64le-ibm-linux-gnu', unknown offloading kind 'openxp', unknown target triple 'pxxerpc64le-ibm-linux-gnu'
 // CK-ERR8: error: invalid target 'xpenmp-x86_xx-pc-linux-gnu', unknown offloading kind 'xpenmp', unknown target triple 'x86_xx-pc-linux-gnu'
 
 // RUN: not clang-offload-bundler -type=i -targets=openmp-powerpc64le-linux,openmp-powerpc64le-ibm-linux-gnu,openmp-x86_64-pc-linux-gnu -inputs=%t.i,%t.tgt1,%t.tgt2 -outputs=%t.bundle.i 2>&1 | FileCheck %s --check-prefix CK-ERR9A
 // RUN: not clang-offload-bundler -type=i -targets=host-%itanium_abi_triple,host-%itanium_abi_triple,openmp-x86_64-pc-linux-gnu -inputs=%t.i,%t.tgt1,%t.tgt2 -outputs=%t.bundle.i 2>&1 | FileCheck %s --check-prefix CK-ERR9B
 // CK-ERR9A: error: expecting exactly one host target but got 0
-// CK-ERR9B: error: expecting exactly one host target but got 2
+// CK-ERR9B: error: Duplicate targets are not allowed
 
 //
 // Check text bundle. This is a readable format, so we check for the format we expect to find.
 //
 // RUN: clang-offload-bundler -type=i -targets=host-%itanium_abi_triple,openmp-powerpc64le-ibm-linux-gnu,openmp-x86_64-pc-linux-gnu -inputs=%t.i,%t.tgt1,%t.tgt2 -outputs=%t.bundle3.i
 // RUN: clang-offload-bundler -type=ii -targets=host-%itanium_abi_triple,openmp-powerpc64le-ibm-linux-gnu,openmp-x86_64-pc-linux-gnu -inputs=%t.ii,%t.tgt1,%t.tgt2 -outputs=%t.bundle3.ii
 // RUN: clang-offload-bundler -type=ll -targets=host-%itanium_abi_triple,openmp-powerpc64le-ibm-linux-gnu,openmp-x86_64-pc-linux-gnu -inputs=%t.ll,%t.tgt1,%t.tgt2 -outputs=%t.bundle3.ll
 // RUN: clang-offload-bundler -type=s -targets=host-%itanium_abi_triple,openmp-powerpc64le-ibm-linux-gnu,openmp-x86_64-pc-linux-gnu -inputs=%t.s,%t.tgt1,%t.tgt2 -outputs=%t.bundle3.s

 // RUN: diff %t.s %t.res.s
 // RUN: diff %t.tgt1 %t.res.tgt1
 // RUN: diff %t.tgt2 %t.res.tgt2
 // RUN: clang-offload-bundler -type=s -targets=openmp-x86_64-pc-linux-gnu -outputs=%t.res.tgt2 -inputs=%t.bundle3.s -unbundle
 // RUN: diff %t.tgt2 %t.res.tgt2
 
 // Check if we can unbundle a file with no magic strings.
 // RUN: clang-offload-bundler -type=s -inputs=%t.s -list | FileCheck -check-prefix=CKLST2 --allow-empty %s
-// RUN: clang-offload-bundler -type=s -targets=host-%itanium_abi_triple,openmp-powerpc64le-ibm-linux-gnu,openmp-x86_64-pc-linux-gnu -outputs=%t.res.s,%t.res.tgt1,%t.res.tgt2 -inputs=%t.s -unbundle
+// RUN: clang-offload-bundler -type=s -targets=host-%itanium_abi_triple,openmp-powerpc64le-ibm-linux-gnu,openmp-x86_64-pc-linux-gnu -outputs=%t.res.s,%t.res.tgt1,%t.res.tgt2 -inputs=%t.s -unbundle -allow-missing-bundles
 // RUN: diff %t.s %t.res.s
 // RUN: diff %t.empty %t.res.tgt1
 // RUN: diff %t.empty %t.res.tgt2
-// RUN: clang-offload-bundler -type=s -targets=openmp-powerpc64le-ibm-linux-gnu,host-%itanium_abi_triple,openmp-x86_64-pc-linux-gnu -outputs=%t.res.tgt1,%t.res.s,%t.res.tgt2 -inputs=%t.s -unbundle
+// RUN: clang-offload-bundler -type=s -targets=openmp-powerpc64le-ibm-linux-gnu,host-%itanium_abi_triple,openmp-x86_64-pc-linux-gnu -outputs=%t.res.tgt1,%t.res.s,%t.res.tgt2 -inputs=%t.s -unbundle -allow-missing-bundles
 // RUN: diff %t.s %t.res.s
 // RUN: diff %t.empty %t.res.tgt1
 // RUN: diff %t.empty %t.res.tgt2
 
 // Check that bindler prints an error if given host bundle does not exist in the fat binary.
-// RUN: not clang-offload-bundler -type=s -targets=host-x86_64-xxx-linux-gnu,openmp-powerpc64le-ibm-linux-gnu -outputs=%t.res.s,%t.res.tgt1 -inputs=%t.bundle3.s -unbundle 2>&1 | FileCheck %s --check-prefix CK-NO-HOST-BUNDLE
+// RUN: not clang-offload-bundler -type=s -targets=host-x86_64-xxx-linux-gnu,openmp-powerpc64le-ibm-linux-gnu -outputs=%t.res.s,%t.res.tgt1 -inputs=%t.bundle3.s -unbundle -allow-missing-bundles 2>&1 | FileCheck %s --check-prefix CK-NO-HOST-BUNDLE
 // CK-NO-HOST-BUNDLE: error: Can't find bundle for the host target
 
 //
 // Check binary bundle/unbundle. The content that we have before bundling must be the same we have after unbundling.
 //
 // RUN: clang-offload-bundler -type=bc -targets=host-%itanium_abi_triple,openmp-powerpc64le-ibm-linux-gnu,openmp-x86_64-pc-linux-gnu -inputs=%t.bc,%t.tgt1,%t.tgt2 -outputs=%t.bundle3.bc
 // RUN: clang-offload-bundler -type=gch -targets=host-%itanium_abi_triple,openmp-powerpc64le-ibm-linux-gnu,openmp-x86_64-pc-linux-gnu -inputs=%t.ast,%t.tgt1,%t.tgt2 -outputs=%t.bundle3.gch
 // RUN: clang-offload-bundler -type=ast -targets=host-%itanium_abi_triple,openmp-powerpc64le-ibm-linux-gnu,openmp-x86_64-pc-linux-gnu -inputs=%t.ast,%t.tgt1,%t.tgt2 -outputs=%t.bundle3.ast

 // RUN: clang-offload-bundler -type=ast -targets=openmp-powerpc64le-ibm-linux-gnu,host-%itanium_abi_triple,openmp-x86_64-pc-linux-gnu -outputs=%t.res.tgt1,%t.res.ast,%t.res.tgt2 -inputs=%t.bundle3.unordered.ast -unbundle
 // RUN: diff %t.ast %t.res.ast
 // RUN: diff %t.tgt1 %t.res.tgt1
 // RUN: diff %t.tgt2 %t.res.tgt2
 // RUN: clang-offload-bundler -type=ast -targets=openmp-powerpc64le-ibm-linux-gnu -outputs=%t.res.tgt1 -inputs=%t.bundle3.ast -unbundle
 // RUN: diff %t.tgt1 %t.res.tgt1
 
 // Check if we can unbundle a file with no magic strings.
-// RUN: clang-offload-bundler -type=bc -targets=host-%itanium_abi_triple,openmp-powerpc64le-ibm-linux-gnu,openmp-x86_64-pc-linux-gnu -outputs=%t.res.bc,%t.res.tgt1,%t.res.tgt2 -inputs=%t.bc -unbundle
+// RUN: clang-offload-bundler -type=bc -targets=host-%itanium_abi_triple,openmp-powerpc64le-ibm-linux-gnu,openmp-x86_64-pc-linux-gnu -outputs=%t.res.bc,%t.res.tgt1,%t.res.tgt2 -inputs=%t.bc -unbundle -allow-missing-bundles
 // RUN: diff %t.bc %t.res.bc
 // RUN: diff %t.empty %t.res.tgt1
 // RUN: diff %t.empty %t.res.tgt2
-// RUN: clang-offload-bundler -type=bc -targets=openmp-powerpc64le-ibm-linux-gnu,host-%itanium_abi_triple,openmp-x86_64-pc-linux-gnu -outputs=%t.res.tgt1,%t.res.bc,%t.res.tgt2 -inputs=%t.bc -unbundle
+// RUN: clang-offload-bundler -type=bc -targets=openmp-powerpc64le-ibm-linux-gnu,host-%itanium_abi_triple,openmp-x86_64-pc-linux-gnu -outputs=%t.res.tgt1,%t.res.bc,%t.res.tgt2 -inputs=%t.bc -unbundle -allow-missing-bundles
 // RUN: diff %t.bc %t.res.bc
 // RUN: diff %t.empty %t.res.tgt1
 // RUN: diff %t.empty %t.res.tgt2
 
 // Check that we do not have to unbundle all available bundles from the fat binary.
 // RUN: clang-offload-bundler -type=ast -targets=host-%itanium_abi_triple,openmp-x86_64-pc-linux-gnu -outputs=%t.res.ast,%t.res.tgt2 -inputs=%t.bundle3.unordered.ast -unbundle
 // RUN: diff %t.ast %t.res.ast
 // RUN: diff %t.tgt2 %t.res.tgt2

 // RUN: diff %t.bundle3.o %t.res.o
 // RUN: diff %t.tgt1 %t.res.tgt1
 // RUN: diff %t.tgt2 %t.res.tgt2
 // RUN: clang-offload-bundler -type=o -targets=openmp-powerpc64le-ibm-linux-gnu -outputs=%t.res.tgt1 -inputs=%t.bundle3.o -unbundle
 // RUN: diff %t.tgt1 %t.res.tgt1
 
 // Check if we can unbundle a file with no magic strings.
 // RUN: clang-offload-bundler -type=o -inputs=%t.o -list | FileCheck -check-prefix=CKLST2 --allow-empty %s
-// RUN: clang-offload-bundler -type=o -targets=host-%itanium_abi_triple,openmp-powerpc64le-ibm-linux-gnu,openmp-x86_64-pc-linux-gnu -outputs=%t.res.o,%t.res.tgt1,%t.res.tgt2 -inputs=%t.o -unbundle
+// RUN: clang-offload-bundler -type=o -targets=host-%itanium_abi_triple,openmp-powerpc64le-ibm-linux-gnu,openmp-x86_64-pc-linux-gnu -outputs=%t.res.o,%t.res.tgt1,%t.res.tgt2 -inputs=%t.o -unbundle -allow-missing-bundles
 // RUN: diff %t.o %t.res.o
 // RUN: diff %t.empty %t.res.tgt1
 // RUN: diff %t.empty %t.res.tgt2
-// RUN: clang-offload-bundler -type=o -targets=openmp-powerpc64le-ibm-linux-gnu,host-%itanium_abi_triple,openmp-x86_64-pc-linux-gnu -outputs=%t.res.tgt1,%t.res.o,%t.res.tgt2 -inputs=%t.o -unbundle
+// RUN: clang-offload-bundler -type=o -targets=openmp-powerpc64le-ibm-linux-gnu,host-%itanium_abi_triple,openmp-x86_64-pc-linux-gnu -outputs=%t.res.tgt1,%t.res.o,%t.res.tgt2 -inputs=%t.o -unbundle -allow-missing-bundles
 // RUN: diff %t.o %t.res.o
 // RUN: diff %t.empty %t.res.tgt1
 // RUN: diff %t.empty %t.res.tgt2
 
 //
 // Check -bundle-align option
 //
 

 // CKLST-DAG: host-
 // CKLST-DAG: openmp-powerpc64le-ibm-linux-gnu
 // CKLST-DAG: openmp-x86_64-pc-linux-gnu
 
 // CKLST2-NOT: host-
 // CKLST2-NOT: openmp-powerpc64le-ibm-linux-gnu
 // CKLST2-NOT: openmp-x86_64-pc-linux-gnu
 
+//
+// Check error due to missing bundles
+//
+// RUN: clang-offload-bundler -type=bc -targets=host-%itanium_abi_triple,hip-amdgcn-amd-amdhsa-gfx900 -inputs=%t.bc,%t.tgt1 -outputs=%t.hip.bundle.bc
+// RUN: not clang-offload-bundler -type=bc -inputs=%t.hip.bundle.bc -outputs=%t.tmp.bc -unbundle \
+// RUN:   -targets=hip-amdgcn-amd-amdhsa-gfx906 \
+// RUN:   2>&1 | FileCheck -check-prefix=MISS1 %s
+// RUN: not clang-offload-bundler -type=bc -inputs=%t.hip.bundle.bc -outputs=%t.tmp.bc,%t.tmp2.bc -unbundle \
+// RUN:   -targets=hip-amdgcn-amd-amdhsa-gfx906,hip-amdgcn-amd-amdhsa-gfx900 \
+// RUN:   2>&1 | FileCheck -check-prefix=MISS1 %s
+// MISS1: error: Can't find bundles for hip-amdgcn-amd-amdhsa-gfx906
+// RUN: not clang-offload-bundler -type=bc -inputs=%t.hip.bundle.bc -outputs=%t.tmp.bc,%t.tmp2.bc -unbundle \
+// RUN:   -targets=hip-amdgcn-amd-amdhsa-gfx906,hip-amdgcn-amd-amdhsa-gfx803 \
+// RUN:   2>&1 | FileCheck -check-prefix=MISS2 %s
+// MISS2: error: Can't find bundles for hip-amdgcn-amd-amdhsa-gfx803 and hip-amdgcn-amd-amdhsa-gfx906
+// RUN: not clang-offload-bundler -type=bc -inputs=%t.hip.bundle.bc -outputs=%t.tmp.bc,%t.tmp2.bc,%t.tmp3.bc -unbundle \
+// RUN:   -targets=hip-amdgcn-amd-amdhsa-gfx906,hip-amdgcn-amd-amdhsa-gfx803,hip-amdgcn-amd-amdhsa-gfx1010 \
+// RUN:   2>&1 | FileCheck -check-prefix=MISS3 %s
+// MISS3: error: Can't find bundles for hip-amdgcn-amd-amdhsa-gfx1010, hip-amdgcn-amd-amdhsa-gfx803, and hip-amdgcn-amd-amdhsa-gfx906
+
+//
+// Check error due to duplicate targets
+//
+// RUN: not clang-offload-bundler -type=bc -targets=host-%itanium_abi_triple,hip-amdgcn-amd-amdhsa-gfx900,hip-amdgcn-amd-amdhsa-gfx900 \
+// RUN:   -inputs=%t.bc,%t.tgt1,%t.tgt1 -outputs=%t.hip.bundle.bc 2>&1 | FileCheck -check-prefix=DUP %s
+// RUN: not clang-offload-bundler -type=bc -inputs=%t.hip.bundle.bc -outputs=%t.tmp.bc,%t.tmp2.bc -unbundle \
+// RUN:   -targets=hip-amdgcn-amd-amdhsa-gfx906,hip-amdgcn-amd-amdhsa-gfx906 \
+// RUN:   2>&1 | FileCheck -check-prefix=DUP %s
+// DUP: error: Duplicate targets are not allowed
+
 // Some code so that we can create a binary out of this file.
 int A = 0;
 void test_func(void) {
   ++A;
 }

clang/test/Driver/hip-toolchain-rdc-separate.hip

 // RUN:   --cuda-gpu-arch=gfx803 --cuda-gpu-arch=gfx900 \
 // RUN:   -fuse-ld=lld -fgpu-rdc -nogpuinc \
 // RUN:   %T/a.o %T/b.o \
 // RUN: 2>&1 | FileCheck -check-prefix=LINK %s
 
 // LINK: [[BUNDLER:".*clang-offload-bundler"]] "-type=o"
 // LINK-SAME: "-targets=host-x86_64-unknown-linux-gnu,hip-amdgcn-amd-amdhsa-gfx803,hip-amdgcn-amd-amdhsa-gfx900"
 // LINK-SAME: "-inputs=[[A_O:.*a.o]]" "-outputs=[[A_OBJ_HOST:.*o]],{{.*o}},{{.*o}}"
-// LINK: "-unbundle"
+// LINK: "-unbundle" "-allow-missing-bundles"
 
 // LINK: [[BUNDLER:".*clang-offload-bundler"]] "-type=o"
 // LINK-SAME: "-targets=host-x86_64-unknown-linux-gnu,hip-amdgcn-amd-amdhsa-gfx803,hip-amdgcn-amd-amdhsa-gfx900"
 // LINK-SAME: "-inputs=[[B_O:.*b.o]]" "-outputs=[[B_OBJ_HOST:.*o]],{{.*o}},{{.*o}}"
-// LINK: "-unbundle"
+// LINK: "-unbundle" "-allow-missing-bundles"
 
 // LINK: [[BUNDLER:".*clang-offload-bundler"]] "-type=o"
 // LINK-SAME: "-targets=host-x86_64-unknown-linux-gnu,hip-amdgcn-amd-amdhsa-gfx803,hip-amdgcn-amd-amdhsa-gfx900"
 // LINK-SAME: "-inputs=[[A_O]]" "-outputs={{.*o}},[[A_BC1:.*o]],[[A_BC2:.*o]]"
-// LINK: "-unbundle"
+// LINK: "-unbundle" "-allow-missing-bundles"
 
 // LINK: [[BUNDLER:".*clang-offload-bundler"]] "-type=o"
 // LINK-SAME: "-targets=host-x86_64-unknown-linux-gnu,hip-amdgcn-amd-amdhsa-gfx803,hip-amdgcn-amd-amdhsa-gfx900"
 // LINK-SAME: "-inputs=[[B_O]]" "-outputs={{.*o}},[[B_BC1:.*o]],[[B_BC2:.*o]]"
-// LINK: "-unbundle"
+// LINK: "-unbundle" "-allow-missing-bundles"
 
 // LINK-NOT: "*.llvm-link"
 // LINK-NOT: ".*opt"
 // LINK-NOT: ".*llc"
 // LINK: {{".*lld.*"}} {{.*}} "-plugin-opt=-amdgpu-internalize-symbols"
 // LINK: "-plugin-opt=mcpu=gfx803"
 // LINK-SAME: "-o" "[[IMG_DEV1:.*.out]]" "[[A_BC1]]" "[[B_BC1]]"
 

clang/test/Driver/openmp-offload.c

 // RUN:   %clang -### -fopenmp=libomp -o %t.out -lsomelib -target powerpc64le-linux -fopenmp-targets=powerpc64le-ibm-linux-gnu,x86_64-pc-linux-gnu %t.o %S/Inputs/in.so -save-temps -no-canonical-prefixes 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHK-UBJOBS2-ST %s
 
 // Unbundle and create host BC.
 // CHK-UBJOBS: clang-offload-bundler{{.*}}" "-type=i" "-targets=host-powerpc64le-unknown-linux,openmp-powerpc64le-ibm-linux-gnu,openmp-x86_64-pc-linux-gnu" "-inputs=
 // CHK-UBJOBS-SAME: [[INPUT:[^\\/]+\.i]]" "-outputs=
 // CHK-UBJOBS-SAME: [[HOSTPP:[^\\/]+\.i]],
 // CHK-UBJOBS-SAME: [[T1PP:[^\\/]+\.i]],
-// CHK-UBJOBS-SAME: [[T2PP:[^\\/]+\.i]]" "-unbundle"
+// CHK-UBJOBS-SAME: [[T2PP:[^\\/]+\.i]]" "-unbundle" "-allow-missing-bundles"
 // CHK-UBJOBS: clang{{.*}}" "-cc1" "-triple" "powerpc64le-unknown-linux" {{.*}}"-emit-llvm-bc" {{.*}}"-fopenmp" {{.*}}"-disable-llvm-passes" {{.*}}"-fopenmp-targets=powerpc64le-ibm-linux-gnu,x86_64-pc-linux-gnu" {{.*}}"-o" "
 // CHK-UBJOBS-SAME: [[HOSTBC:[^\\/]+\.bc]]" "-x" "cpp-output" "{{.*}}[[HOSTPP]]"
 // CHK-UBJOBS: clang{{.*}}" "-cc1" "-triple" "powerpc64le-unknown-linux" {{.*}}"-emit-obj" {{.*}}"-fopenmp" {{.*}}"-o" "
 // CHK-UBJOBS-SAME: [[HOSTOBJ:[^\\/]+\.o]]" "-x" "ir" "{{.*}}[[HOSTBC]]"
 // CHK-UBJOBS-ST: clang-offload-bundler{{.*}}" "-type=i" "-targets=host-powerpc64le-unknown-linux,openmp-powerpc64le-ibm-linux-gnu,openmp-x86_64-pc-linux-gnu" "-inputs=
 // CHK-UBJOBS-ST-SAME: [[INPUT:[^\\/]+\.i]]" "-outputs=
 // CHK-UBJOBS-ST-SAME: [[HOSTPP:[^\\/,]+\.i]],
 // CHK-UBJOBS-ST-SAME: [[T1PP:[^\\/,]+\.i]],
-// CHK-UBJOBS-ST-SAME: [[T2PP:[^\\/,]+\.i]]" "-unbundle"
+// CHK-UBJOBS-ST-SAME: [[T2PP:[^\\/,]+\.i]]" "-unbundle" "-allow-missing-bundles"
 // CHK-UBJOBS-ST: clang{{.*}}" "-cc1" "-triple" "powerpc64le-unknown-linux" {{.*}}"-emit-llvm-bc" {{.*}}"-fopenmp" {{.*}}"-disable-llvm-passes" {{.*}}"-fopenmp-targets=powerpc64le-ibm-linux-gnu,x86_64-pc-linux-gnu" {{.*}}"-o" "
 // CHK-UBJOBS-ST-SAME: [[HOSTBC:[^\\/]+\.bc]]" "-x" "cpp-output" "{{.*}}[[HOSTPP]]"
 // CHK-UBJOBS-ST: clang{{.*}}" "-cc1" "-triple" "powerpc64le-unknown-linux" {{.*}}"-S" {{.*}}"-fopenmp" {{.*}}"-o" "
 // CHK-UBJOBS-ST-SAME: [[HOSTASM:[^\\/]+\.s]]" "-x" "ir" "{{.*}}[[HOSTBC]]"
 // CHK-UBJOBS-ST: clang{{.*}}" "-cc1as" "-triple" "powerpc64le-unknown-linux" "-filetype" "obj" {{.*}}"-o" "
 // CHK-UBJOBS-ST-SAME: [[HOSTOBJ:[^\\/]+\.o]]" "{{.*}}[[HOSTASM]]"
 
 // Create target 1 object.

 // CHK-UBJOBS-ST: ld{{(\.exe)?}}" {{.*}}"-o" "
 // CHK-UBJOBS-ST-SAME: [[HOSTBIN:[^\\/]+\.out]]" {{.*}}"{{.*}}[[HOSTOBJ]]" "{{.*}}[[WRAPPEROBJ]]"
 
 // Unbundle object file.
 // CHK-UBJOBS2: clang-offload-bundler{{.*}}" "-type=o" "-targets=host-powerpc64le-unknown-linux,openmp-powerpc64le-ibm-linux-gnu,openmp-x86_64-pc-linux-gnu" "-inputs=
 // CHK-UBJOBS2-SAME: [[INPUT:[^\\/]+\.o]]" "-outputs=
 // CHK-UBJOBS2-SAME: [[HOSTOBJ:[^\\/]+\.o]],
 // CHK-UBJOBS2-SAME: [[T1OBJ:[^\\/]+\.o]],
-// CHK-UBJOBS2-SAME: [[T2OBJ:[^\\/]+\.o]]" "-unbundle"
+// CHK-UBJOBS2-SAME: [[T2OBJ:[^\\/]+\.o]]" "-unbundle" "-allow-missing-bundles"
 // CHK-UBJOBS2: ld{{(\.exe)?}}" {{.*}}"-o" "
 // CHK-UBJOBS2-SAME: [[T1BIN:[^\\/]+\.out]]" {{.*}}"{{.*}}[[T1OBJ]]"
 // CHK-UBJOBS2: ld{{(\.exe)?}}" {{.*}}"-o" "
 // CHK-UBJOBS2-SAME: [[T2BIN:[^\\/]+\.out]]" {{.*}}"{{.*}}[[T2OBJ]]"
 // CHK-UBJOBS2: clang-offload-wrapper{{(\.exe)?}}" "-target" "powerpc64le-unknown-linux" {{.*}}"-o" "
 // CHK-UBJOBS2-SAME: [[WRAPPERBC:[^\\/]+\.bc]]" "{{.*}}[[T1BIN]]" "{{.*}}[[T2BIN]]"
 // CHK-UBJOBS2: clang{{.*}}" "-cc1" "-triple" "powerpc64le-unknown-linux" {{.*}}"-emit-obj" {{.*}}"-fopenmp" {{.*}}"-o" "
 // CHK-UBJOBS2-SAME: [[WRAPPEROBJ:[^\\/]+\.o]]" "-x" "ir" "{{.*}}[[WRAPPERBC]]"
 // CHK-UBJOBS2: ld{{(\.exe)?}}" {{.*}}"-o" "
 // CHK-UBJOBS2-SAME: [[HOSTBIN:[^\\/]+\.out]]" {{.*}}"{{.*}}[[HOSTOBJ]]" "{{.*}}[[WRAPPEROBJ]]"
 // CHK-UBJOBS2-ST-NOT: clang-offload-bundler{{.*}}in.so
 // CHK-UBJOBS2-ST: clang-offload-bundler{{.*}}" "-type=o" "-targets=host-powerpc64le-unknown-linux,openmp-powerpc64le-ibm-linux-gnu,openmp-x86_64-pc-linux-gnu" "-inputs=
 // CHK-UBJOBS2-ST-SAME: [[INPUT:[^\\/]+\.o]]" "-outputs=
 // CHK-UBJOBS2-ST-SAME: [[HOSTOBJ:[^\\/,]+\.o]],
 // CHK-UBJOBS2-ST-SAME: [[T1OBJ:[^\\/,]+\.o]],
-// CHK-UBJOBS2-ST-SAME: [[T2OBJ:[^\\/,]+\.o]]" "-unbundle"
+// CHK-UBJOBS2-ST-SAME: [[T2OBJ:[^\\/,]+\.o]]" "-unbundle" "-allow-missing-bundles"
 // CHK-UBJOBS2-ST-NOT: clang-offload-bundler{{.*}}in.so
 // CHK-UBJOBS2-ST: ld{{(\.exe)?}}" {{.*}}"-o" "
 // CHK-UBJOBS2-ST-SAME: [[T1BIN:[^\\/]+\.out-openmp-powerpc64le-ibm-linux-gnu]]" {{.*}}"{{.*}}[[T1OBJ]]"
 // CHK-UBJOBS2-ST: ld{{(\.exe)?}}" {{.*}}"-o" "
 // CHK-UBJOBS2-ST-SAME: [[T2BIN:[^\\/]+\.out-openmp-x86_64-pc-linux-gnu]]" {{.*}}"{{.*}}[[T2OBJ]]"
 // CHK-UBJOBS2-ST: clang-offload-wrapper{{(\.exe)?}}" "-target" "powerpc64le-unknown-linux" {{.*}}"-o" "
 // CHK-UBJOBS2-ST-SAME: [[WRAPPERBC:[^\\/]+\.bc]]" "{{.*}}[[T1BIN]]" "{{.*}}[[T2BIN]]"
 // CHK-UBJOBS2-ST: clang{{.*}}" "-cc1" "-triple" "powerpc64le-unknown-linux" {{.*}}"-S" {{.*}}"-fopenmp" {{.*}}"-o" "

 // RUN:   %clang -### -fopenmp=libomp -c %t.o -lsomelib -target powerpc64le-linux -fopenmp-targets=powerpc64le-ibm-linux-gnu,x86_64-pc-linux-gnu %t.i -save-temps -no-canonical-prefixes 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHK-UBUJOBS-ST %s
 
 // Unbundle and create host BC.
 // CHK-UBUJOBS: clang-offload-bundler{{.*}}" "-type=i" "-targets=host-powerpc64le-unknown-linux,openmp-powerpc64le-ibm-linux-gnu,openmp-x86_64-pc-linux-gnu" "-inputs=
 // CHK-UBUJOBS-SAME: [[INPUT:[^\\/]+\.i]]" "-outputs=
 // CHK-UBUJOBS-SAME: [[HOSTPP:[^\\/]+\.i]],
 // CHK-UBUJOBS-SAME: [[T1PP:[^\\/]+\.i]],
-// CHK-UBUJOBS-SAME: [[T2PP:[^\\/]+\.i]]" "-unbundle"
+// CHK-UBUJOBS-SAME: [[T2PP:[^\\/]+\.i]]" "-unbundle" "-allow-missing-bundles"
 // CHK-UBUJOBS: clang{{.*}}" "-cc1" "-triple" "powerpc64le-unknown-linux" {{.*}}"-emit-llvm-bc" {{.*}}"-fopenmp" {{.*}}"-disable-llvm-passes" {{.*}}"-fopenmp-targets=powerpc64le-ibm-linux-gnu,x86_64-pc-linux-gnu" {{.*}}"-o" "
 // CHK-UBUJOBS-SAME: [[HOSTBC:[^\\/]+\.bc]]" "-x" "cpp-output" "{{.*}}[[HOSTPP]]"
 
 // CHK-UBUJOBS-ST: clang-offload-bundler{{.*}}" "-type=i" "-targets=host-powerpc64le-unknown-linux,openmp-powerpc64le-ibm-linux-gnu,openmp-x86_64-pc-linux-gnu" "-inputs=
 // CHK-UBUJOBS-ST-SAME: [[INPUT:[^\\/]+\.i]]" "-outputs=
 // CHK-UBUJOBS-ST-SAME: [[HOSTPP:[^\\/,]+\.i]],
 // CHK-UBUJOBS-ST-SAME: [[T1PP:[^\\/,]+\.i]],
-// CHK-UBUJOBS-ST-SAME: [[T2PP:[^\\/,]+\.i]]" "-unbundle"
+// CHK-UBUJOBS-ST-SAME: [[T2PP:[^\\/,]+\.i]]" "-unbundle" "-allow-missing-bundles"
 // CHK-UBUJOBS-ST: clang{{.*}}" "-cc1" "-triple" "powerpc64le-unknown-linux" {{.*}}"-emit-llvm-bc" {{.*}}"-fopenmp" {{.*}}"-disable-llvm-passes" {{.*}}"-fopenmp-targets=powerpc64le-ibm-linux-gnu,x86_64-pc-linux-gnu" {{.*}}"-o" "
 // CHK-UBUJOBS-ST-SAME: [[HOSTBC:[^\\/]+\.bc]]" "-x" "cpp-output" "{{.*}}[[HOSTPP]]"
 
 // Create target 1 object.
 // CHK-UBUJOBS: clang{{.*}}" "-cc1" "-triple" "powerpc64le-ibm-linux-gnu" "-aux-triple" "powerpc64le-unknown-linux" {{.*}}"-emit-obj" {{.*}}"-fopenmp" {{.*}}"-fopenmp-is-device" "-fopenmp-host-ir-file-path" "{{.*}}[[HOSTBC]]" {{.*}}"-o" "
 // CHK-UBUJOBS-SAME: [[T1OBJ:[^\\/]+\.o]]" "-x" "cpp-output" "{{.*}}[[T1PP]]"
 // CHK-UBUJOBS-ST: clang{{.*}}" "-cc1" "-triple" "powerpc64le-ibm-linux-gnu" "-aux-triple" "powerpc64le-unknown-linux" {{.*}}"-emit-llvm-bc" {{.*}}"-fopenmp" {{.*}}"-fopenmp-is-device" "-fopenmp-host-ir-file-path" "{{.*}}[[HOSTBC]]" {{.*}}"-o" "
 // CHK-UBUJOBS-ST-SAME: [[T1BC:[^\\/]+\.bc]]" "-x" "cpp-output" "{{.*}}[[T1PP]]"

clang/tools/clang-offload-bundler/ClangOffloadBundler.cpp

 #include "llvm/Support/WithColor.h"
 #include "llvm/Support/raw_ostream.h"
 #include <algorithm>
 #include <cassert>
 #include <cstddef>
 #include <cstdint>
 #include <forward_list>
 #include <memory>
+#include <set>
 #include <string>
 #include <system_error>
 #include <utility>
 
 using namespace llvm;
 using namespace llvm::object;
 
 static cl::opt<bool> Help("h", cl::desc("Alias for -help"), cl::Hidden);
ListBundleIDs("list", cl::desc("List bundle IDs in the bundled file.\n"),
                   cl::init(false), cl::cat(ClangOffloadBundlerCategory));
 
 static cl::opt<bool> PrintExternalCommands(
     "###",
     cl::desc("Print any external commands that are to be executed "
              "instead of actually executing them - for testing purposes.\n"),
     cl::init(false), cl::cat(ClangOffloadBundlerCategory));
 
+static cl::opt<bool>
+    AllowMissingBundles("allow-missing-bundles",
+                        cl::desc("Create empty files if bundles are missing "
+                                 "when unbundling.\n"),
+                        cl::init(false), cl::cat(ClangOffloadBundlerCategory));
+
 static cl::opt<unsigned>
     BundleAlignment("bundle-align",
                     cl::desc("Alignment of bundle for binary files"),
                     cl::init(1), cl::cat(ClangOffloadBundlerCategory));
 
 /// Magic string that marks the existence of offloading data.
 #define OFFLOAD_BUNDLER_MAGIC_STR "__CLANG_OFFLOAD_BUNDLE__"
 
if (Error Err = FH->ReadBundleEnd(Input))
       return Err;
     Worklist.erase(Output);
 
     // Record if we found the host bundle.
     if (hasHostKind(CurTriple))
       FoundHostBundle = true;
   }
 
+  if (!AllowMissingBundles && !Worklist.empty()) {
+    std::string ErrMsg = "Can't find bundles for";
+    std::set<StringRef> Sorted;
+    for (auto &E : Worklist)
+      Sorted.insert(E.first());
+    unsigned I = 0;
+    unsigned Last = Worklist.size() - 1;
+    for (auto &E : Sorted) {
+      if (I != 0 && Last > 1)
+        ErrMsg += ",";
+      ErrMsg += " ";
+      if (I == Last && I != 0)
+        ErrMsg += "and ";
+      ErrMsg += E.str();
+      ++I;
+    }
+    return createStringError(inconvertibleErrorCode(), ErrMsg);
+  }
+
   // If no bundles were found, assume the input file is the host bundle and
   // create empty files for the remaining targets.
   if (Worklist.size() == TargetNames.size()) {
     for (auto &E : Worklist) {
       std::error_code EC;
       raw_fd_ostream OutputFile(E.second, EC, sys::fs::OF_None);
       if (EC)
         return createFileError(E.second, EC);
 
       // If this entry has a host kind, copy the input file to the output file.
if (InputFileNames.size() != TargetNames.size()) {
           "number of input files and targets should match in bundling mode"));
     }
   }
 
   // Verify that the offload kinds and triples are known. We also check that we
   // have exactly one host target.
   unsigned Index = 0u;
   unsigned HostTargetNum = 0u;
+  llvm::DenseSet<StringRef> ParsedTargets;
   for (StringRef Target : TargetNames) {
+    if (ParsedTargets.count(Target)) {
+      reportError(createStringError(errc::invalid_argument,
+                                    "Duplicate targets are not allowed"));
+      return 1;
+    }
+    ParsedTargets.insert(Target);
+
     StringRef Kind;
     StringRef Triple;
     getOffloadKindAndTriple(Target, Kind, Triple);
 
     bool KindIsValid = !Kind.empty();
     KindIsValid = KindIsValid && StringSwitch<bool>(Kind)
                                      .Case("host", true)
                                      .Case("openmp", true)