Use dynamic lookup to prevent Enzyme from embedding its own copy of LLVM on APPLE

.github/workflows/enzyme-rust.yml

@@ -0,0 +1,91 @@
+name: Rust Enzyme CI
+
+on:
+  push:
+    branches:
+    - main
+  pull_request:
+    branches:
+    - main
+  merge_group:
+
+jobs:
+  build:
+    name: Enzyme CI Rust ${{ matrix.os }} - ${{ matrix.rust-version }}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os:
+          - ubuntu-latest
+          #- macOS-latest # broken: https://github.com/rust-lang/enzyme/actions/runs/18791780110/job/53623553780?pr=30
+        rust-version:
+          - master
+          - b2ee1b333aea9951c3eefa4967098cc763de59ca
+    steps:
+      - name: Clone rust
+        run: |
+          git clone --depth=1 https://github.com/rust-lang/rust .
+      - name: Adjust git settings
+        run: |
+          git config --global user.email "ci@example.org"
+          git config --global user.name  "CI"
+
+      # Infra: Setup caching using ccache
+      - name: Install ccache (Linux)
+        if: runner.os == 'Linux'
+        run: |
+          sudo apt update && sudo apt install -y ccache
+      - name: Install ccache (macOS)
+        if: runner.os == 'macOS'
+        run: |
+          brew install ccache
+      - name: Get LLVM project commit SHA for use as cache key
+        id: llvm-commit
+        run: |
+          COMMIT_HASH="$(git ls-tree --object-only HEAD src/llvm-project)"
+          echo "LLVM should be on commit: '$COMMIT_HASH'"
+          echo "commit_hash=$COMMIT_HASH" >> $GITHUB_OUTPUT
+      - name: Cache ccache
+        id: cache-ccache
+        uses: actions/cache@v4
+        with:
+          path: ~/.cache/ccache
+          key: ${{ runner.os }}-ccache-${{ steps['llvm-commit'].outputs.commit_hash }}
+          # We fall back to *any* cache. It is ccache, it can handle invalidation
+          # and eviction on its own. TODO: We might want to limit its size / use
+          # evict-older-than?
+          restore-keys: |
+            ${{ runner.os }}-ccache-${{ steps['llvm-commit'].outputs.commit_hash }}
+            ${{ runner.os }}-ccache-
+
+      # Now we get to the actual meat. Initialize enzyme at $GITHUB_SHA to ensure we
+      # actually test the right commit :)
+      - name: Init enzyme submodule
+        run: |
+          git submodule update --init src/tools/enzyme
+      - name: Update enzyme submodule
+        run: |
+          pushd src/tools/enzyme || exit 1
+          git fetch origin $GITHUB_SHA
+          git checkout $GITHUB_SHA
+          popd || exit 1
+
+          git add src/tools/enzyme && git commit -m "Set Enzyme version"
+
+      # And now we build!
+      - name: Configure
+        run: |
+          ./configure --release-channel=nightly --enable-llvm-enzyme --enable-llvm-assertions --enable-option-checking --disable-docs --enable-ccache
+      - name: Inspect ccache
+        run: |
+          ccache --show-config
+          ccache --show-stats
+          ccache --zero-stats  # rebaseline
+      - name: Build
+        run: |
+          ./x build --stage 1 library
+      - name: Inspect ccache
+        run: |
+          ccache --show-config
+          ccache --show-stats

.gitignore

@@ -8,6 +8,7 @@ enzyme/benchmarks/ReverseMode/*/*.ll
 enzyme/benchmarks/ReverseMode/*/*.bc
 enzyme/benchmarks/ReverseMode/*/*.o
 enzyme/benchmarks/ReverseMode/*/*.exe
+enzyme/benchmarks/ReverseMode/*/target/
 enzyme/benchmarks/ReverseMode/*/results.txt
 enzyme/benchmarks/ReverseMode/*/results.json
 .cache

enzyme/Enzyme/CMakeLists.txt

@@ -145,7 +145,16 @@ if (${ENZYME_EXTERNAL_SHARED_LIB})
     add_dependencies(Enzyme-${LLVM_VERSION_MAJOR} BlasDeclarationsIncGen)
     add_dependencies(Enzyme-${LLVM_VERSION_MAJOR} BlasTAIncGen)
     add_dependencies(Enzyme-${LLVM_VERSION_MAJOR} BlasDiffUseIncGen)
-    target_link_libraries(Enzyme-${LLVM_VERSION_MAJOR} LLVM)
+
+    if (APPLE)
+        # Use dynamic lookup to prevent Enzyme from embedding its own copy of LLVM on macOS.
+        # rustc already embeds LLVM and having two copies can cause autodiff to hang.
+        target_link_options(Enzyme-${LLVM_VERSION_MAJOR} PRIVATE
+            "-Wl,-flat_namespace"
+            "-Wl,-undefined,dynamic_lookup")
+    else()
+        target_link_libraries(Enzyme-${LLVM_VERSION_MAJOR} LLVM)
+    endif()
     install(TARGETS Enzyme-${LLVM_VERSION_MAJOR}
         EXPORT EnzymeTargets
         LIBRARY DESTINATION lib COMPONENT shlib

enzyme/benchmarks/ReverseMode/adbench/Makefile.config

@@ -0,0 +1,9 @@
+CLANG := /home/manuel/prog/rust-middle/build/x86_64-unknown-linux-gnu/llvm/build/bin/clang++
+OPT := /home/manuel/prog/rust-middle/build/x86_64-unknown-linux-gnu/llvm/build/bin/opt
+
+PASSES1 := verify,annotation2metadata,forceattrs,inferattrs,coro-early,function<eager-inv>(ee-instrument<>,lower-expect,simplifycfg<bonus-inst-threshold=1;no-forward-switch-cond;no-switch-range-to-icmp;no-switch-to-lookup;keep-loops;no-hoist-common-insts;no-hoist-loads-stores-with-cond-faulting;no-sink-common-insts;speculate-blocks;simplify-cond-branch;no-speculate-unpredictables>,sroa<modify-cfg>,early-cse<>,callsite-splitting),openmp-opt,ipsccp,called-value-propagation,globalopt,function<eager-inv>(mem2reg,instcombine<max-iterations=1;no-verify-fixpoint>,simplifycfg<bonus-inst-threshold=1;no-forward-switch-cond;switch-range-to-icmp;no-switch-to-lookup;keep-loops;no-hoist-common-insts;no-hoist-loads-stores-with-cond-faulting;no-sink-common-insts;speculate-blocks;simplify-cond-branch;no-speculate-unpredictables>),always-inline,require<globals-aa>,function(invalidate<aa>),require<profile-summary>,cgscc(devirt<4>(inline,function-attrs<skip-non-recursive-function-attrs>,argpromotion,openmp-opt-cgscc,function<eager-inv;no-rerun>(sroa<modify-cfg>,early-cse<memssa>,speculative-execution<only-if-divergent-target>,jump-threading,correlated-propagation,simplifycfg<bonus-inst-threshold=1;no-forward-switch-cond;switch-range-to-icmp;no-switch-to-lookup;keep-loops;no-hoist-common-insts;no-hoist-loads-stores-with-cond-faulting;no-sink-common-insts;speculate-blocks;simplify-cond-branch;no-speculate-unpredictables>,instcombine<max-iterations=1;no-verify-fixpoint>,aggressive-instcombine,libcalls-shrinkwrap,tailcallelim,simplifycfg<bonus-inst-threshold=1;no-forward-switch-cond;switch-range-to-icmp;no-switch-to-lookup;keep-loops;no-hoist-common-insts;no-hoist-loads-stores-with-cond-faulting;no-sink-common-insts;speculate-blocks;simplify-cond-branch;no-speculate-unpredictables>,reassociate,constraint-elimination,loop-mssa(loop-instsimplify,loop-simplifycfg,licm<no-allowspeculation>,loop-rotate<header-duplication;prepare-for-lto>,licm<allowspeculation>,simple-loop-unswitch<nontrivial;trivial>),simplifycfg<bonus-inst-threshold=1;no-forward-switch-cond;switch-range-to-icmp;no-switch-to-lookup;keep-loops;no-hoist-common-insts;no-hoist-loads-stores-with-cond-faulting;no-sink-common-insts;speculate-blocks;simplify-cond-branch;no-speculate-unpredictables>,instcombine<max-iterations=1;no-verify-fixpoint>,loop(loop-idiom,indvars,extra-simple-loop-unswitch-passes,loop-deletion,loop-unroll-full),sroa<modify-cfg>,vector-combine,mldst-motion<no-split-footer-bb>,gvn<>,sccp,bdce,instcombine<max-iterations=1;no-verify-fixpoint>,jump-threading,correlated-propagation,adce,memcpyopt,dse,move-auto-init,loop-mssa(licm<allowspeculation>),coro-elide,simplifycfg<bonus-inst-threshold=1;no-forward-switch-cond;switch-range-to-icmp;no-switch-to-lookup;keep-loops;hoist-common-insts;no-hoist-loads-stores-with-cond-faulting;sink-common-insts;speculate-blocks;simplify-cond-branch;no-speculate-unpredictables>,instcombine<max-iterations=1;no-verify-fixpoint>),function-attrs,function(require<should-not-run-function-passes>),coro-split,coro-annotation-elide)),deadargelim,coro-cleanup,globalopt,globaldce,rpo-function-attrs,recompute-globalsaa,function<eager-inv>(float2int,lower-constant-intrinsics,chr,loop(loop-rotate<header-duplication;prepare-for-lto>,loop-deletion),loop-distribute,inject-tli-mappings,loop-vectorize<interleave-forced-only;vectorize-forced-only;>,infer-alignment,loop-load-elim,instcombine<max-iterations=1;no-verify-fixpoint>,simplifycfg<bonus-inst-threshold=1;forward-switch-cond;switch-range-to-icmp;switch-to-lookup;no-keep-loops;hoist-common-insts;no-hoist-loads-stores-with-cond-faulting;sink-common-insts;speculate-blocks;simplify-cond-branch;no-speculate-unpredictables>,vector-combine,instcombine<max-iterations=1;no-verify-fixpoint>,loop-unroll<O3>,transform-warning,sroa<preserve-cfg>,infer-alignment,instcombine<max-iterations=1;no-verify-fixpoint>,loop-mssa(licm<allowspeculation>),alignment-from-assumptions,loop-sink,instsimplify,div-rem-pairs,tailcallelim,simplifycfg<bonus-inst-threshold=1;no-forward-switch-cond;switch-range-to-icmp;no-switch-to-lookup;keep-loops;no-hoist-common-insts;hoist-loads-stores-with-cond-faulting;no-sink-common-insts;speculate-blocks;simplify-cond-branch;speculate-unpredictables>),globaldce,constmerge,function(annotation-remarks),canonicalize-aliases,name-anon-globals,verify
+
+PASSES2 := cross-dso-cfi,openmp-opt,globaldce<vfe-linkage-unit-visibility>,inferattrs,function<eager-inv>(callsite-splitting),pgo-icall-prom,cgscc(function-attrs,argpromotion,function(sroa<modify-cfg>)),ipsccp,called-value-propagation,rpo-function-attrs,globalsplit,wholeprogramdevirt,globalopt,function(mem2reg),constmerge,deadargelim,function<eager-inv>(instcombine<max-iterations=1;no-verify-fixpoint>,aggressive-instcombine),expand-variadics,cgscc(inline<only-mandatory>,inline),globalopt,openmp-opt,globaldce<vfe-linkage-unit-visibility>,cgscc(argpromotion),function<eager-inv>(instcombine<max-iterations=1;no-verify-fixpoint>,constraint-elimination,jump-threading,sroa<modify-cfg>,tailcallelim),cgscc(function-attrs),require<globals-aa>,function(invalidate<aa>),cgscc(openmp-opt-cgscc),function<eager-inv>(loop-mssa(licm<allowspeculation>),gvn<>,memcpyopt,dse,move-auto-init,mldst-motion<no-split-footer-bb>,loop(indvars,loop-deletion,loop-unroll-full),loop-distribute,loop-vectorize<interleave-forced-only;vectorize-forced-only;>,infer-alignment,loop-unroll<O3>,transform-warning,sroa<preserve-cfg>,instcombine<max-iterations=1;no-verify-fixpoint>,simplifycfg<bonus-inst-threshold=1;forward-switch-cond;switch-range-to-icmp;switch-to-lookup;no-keep-loops;hoist-common-insts;no-hoist-loads-stores-with-cond-faulting;sink-common-insts;speculate-blocks;simplify-cond-branch;no-speculate-unpredictables>,sccp,instcombine<max-iterations=1;no-verify-fixpoint>,bdce,vector-combine,infer-alignment,instcombine<max-iterations=1;no-verify-fixpoint>,loop-mssa(licm<allowspeculation>),alignment-from-assumptions,jump-threading),lowertypetests,lowertypetests,function(loop-sink,div-rem-pairs,simplifycfg<bonus-inst-threshold=1;no-forward-switch-cond;switch-range-to-icmp;no-switch-to-lookup;keep-loops;hoist-common-insts;no-hoist-loads-stores-with-cond-faulting;no-sink-common-insts;speculate-blocks;simplify-cond-branch;speculate-unpredictables>),elim-avail-extern,globaldce<vfe-linkage-unit-visibility>,rel-lookup-table-converter,cg-profile,function(annotation-remarks),canonicalize-aliases,name-anon-globals
+#PASSES2 := cross-dso-cfi,openmp-opt,globaldce<vfe-linkage-unit-visibility>,inferattrs,function<eager-inv>(callsite-splitting),pgo-icall-prom,cgscc(function-attrs,argpromotion,function(sroa<modify-cfg>)),ipsccp,called-value-propagation,rpo-function-attrs,globalsplit,wholeprogramdevirt,globalopt,function(mem2reg),constmerge,deadargelim,function<eager-inv>(instcombine<max-iterations=1;no-verify-fixpoint>,aggressive-instcombine),expand-variadics,cgscc(inline<only-mandatory>,inline),globalopt,openmp-opt,globaldce<vfe-linkage-unit-visibility>,cgscc(argpromotion),function<eager-inv>(instcombine<max-iterations=1;no-verify-fixpoint>,constraint-elimination,jump-threading,sroa<modify-cfg>,tailcallelim),cgscc(function-attrs),require<globals-aa>,function(invalidate<aa>),cgscc(openmp-opt-cgscc),function<eager-inv>(loop-mssa(licm<allowspeculation>),gvn<>,memcpyopt,dse,move-auto-init,mldst-motion<no-split-footer-bb>,loop(indvars,loop-deletion,loop-unroll-full),loop-distribute,loop-vectorize<interleave-forced-only;vectorize-forced-only;>,infer-alignment,loop-unroll<O3>,transform-warning,sroa<preserve-cfg>,instcombine<max-iterations=1;no-verify-fixpoint>,simplifycfg<bonus-inst-threshold=1;forward-switch-cond;switch-range-to-icmp;switch-to-lookup;no-keep-loops;hoist-common-insts;no-hoist-loads-stores-with-cond-faulting;sink-common-insts;speculate-blocks;simplify-cond-branch;no-speculate-unpredictables>,sccp,instcombine<max-iterations=1;no-verify-fixpoint>,bdce,vector-combine,infer-alignment,instcombine<max-iterations=1;no-verify-fixpoint>,loop-mssa(licm<allowspeculation>),alignment-from-assumptions,jump-threading),lowertypetests,lowertypetests,function(loop-sink,div-rem-pairs,simplifycfg<bonus-inst-threshold=1;no-forward-switch-cond;switch-range-to-icmp;no-switch-to-lookup;keep-loops;hoist-common-insts;no-hoist-loads-stores-with-cond-faulting;no-sink-common-insts;speculate-blocks;simplify-cond-branch;speculate-unpredictables>),elim-avail-extern,globaldce<vfe-linkage-unit-visibility>,rel-lookup-table-converter,cg-profile,function(annotation-remarks),canonicalize-aliases,name-anon-globals,EnzymeNewPM
+
+PASSES3 := cross-dso-cfi,openmp-opt,globaldce<vfe-linkage-unit-visibility>,inferattrs,function<eager-inv>(callsite-splitting),pgo-icall-prom,cgscc(function-attrs,argpromotion,function(sroa<modify-cfg>)),ipsccp,called-value-propagation,rpo-function-attrs,globalsplit,wholeprogramdevirt,globalopt,function(mem2reg),constmerge,deadargelim,function<eager-inv>(instcombine<max-iterations=1;no-verify-fixpoint>,aggressive-instcombine),expand-variadics,cgscc(inline<only-mandatory>,inline),globalopt,openmp-opt,globaldce<vfe-linkage-unit-visibility>,cgscc(argpromotion),function<eager-inv>(instcombine<max-iterations=1;no-verify-fixpoint>,constraint-elimination,jump-threading,sroa<modify-cfg>,tailcallelim),cgscc(function-attrs),require<globals-aa>,function(invalidate<aa>),cgscc(openmp-opt-cgscc),function<eager-inv>(loop-mssa(licm<allowspeculation>),gvn<>,memcpyopt,dse,move-auto-init,mldst-motion<no-split-footer-bb>,loop(indvars,loop-deletion,loop-unroll-full),loop-distribute,loop-vectorize<no-interleave-forced-only;no-vectorize-forced-only;>,infer-alignment,loop-unroll<O3>,transform-warning,sroa<preserve-cfg>,instcombine<max-iterations=1;no-verify-fixpoint>,simplifycfg<bonus-inst-threshold=1;forward-switch-cond;switch-range-to-icmp;switch-to-lookup;no-keep-loops;hoist-common-insts;no-hoist-loads-stores-with-cond-faulting;sink-common-insts;speculate-blocks;simplify-cond-branch;no-speculate-unpredictables>,sccp,instcombine<max-iterations=1;no-verify-fixpoint>,bdce,slp-vectorizer,vector-combine,infer-alignment,instcombine<max-iterations=1;no-verify-fixpoint>,loop-mssa(licm<allowspeculation>),alignment-from-assumptions,jump-threading),lowertypetests,lowertypetests,function(loop-sink,div-rem-pairs,simplifycfg<bonus-inst-threshold=1;no-forward-switch-cond;switch-range-to-icmp;no-switch-to-lookup;keep-loops;hoist-common-insts;no-hoist-loads-stores-with-cond-faulting;no-sink-common-insts;speculate-blocks;simplify-cond-branch;speculate-unpredictables>),elim-avail-extern,globaldce<vfe-linkage-unit-visibility>,mergefunc,rel-lookup-table-converter,cg-profile,function(annotation-remarks),canonicalize-aliases,name-anon-globals