Run icount benchmarks once with softfloat and once with hardfloat

These benchmarks are fast to run, so the time cost here is pretty
minimal. Running softfloat benchmarks just ensures that we don't e.g.
test the performance of `_mm_sqrt_ss` rather than our implementation,
and running without softfloat gives us a way to see the effect of arch
intrinsics.

library/compiler-builtins/libm/.github/workflows/main.yaml

@@ -170,29 +170,7 @@ jobs:
     - name: Run icount benchmarks
       env:
         GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-      run: |
-        set -eux
-        iai_home="iai-home"
-        # Download the baseline from master
-        ./ci/ci-util.py locate-baseline --download --extract
-
-        # Run iai-callgrind benchmarks
-        cargo bench --no-default-features \
-          --features unstable,unstable-float,icount \
-          --bench icount \
-          -- \
-          --save-baseline=default \
-          --home "$(pwd)/$iai_home" \
-          --regression='ir=5.0' \
-          --save-summary
-        # NB: iai-callgrind should exit on error but does not, so we inspect the sumary
-        # for errors. See  https://github.com/iai-callgrind/iai-callgrind/issues/337
-        ./ci/ci-util.py check-regressions "$iai_home"
-
-        # Name and tar the new baseline
-        name="baseline-icount-$(date -u +'%Y%m%d%H%M')-${GITHUB_SHA:0:12}"
-        echo "BASELINE_NAME=$name" >> "$GITHUB_ENV"
-        tar cJf "$name.tar.xz" "$iai_home"
+      run: ./ci/bench-icount.sh
 
     - name: Upload the benchmark baseline
       uses: actions/upload-artifact@v4

library/compiler-builtins/libm/ci/bench-icount.sh

@@ -0,0 +1,53 @@
+#!/bin/bash
+
+set -eux
+
+iai_home="iai-home"
+
+# Download the baseline from master
+./ci/ci-util.py locate-baseline --download --extract
+
+# Run benchmarks once 
+function run_icount_benchmarks() {
+    cargo_args=(
+        "--bench" "icount"
+        "--no-default-features"
+        "--features" "unstable,unstable-float,icount"
+    )
+
+    iai_args=(
+        "--home" "$(pwd)/$iai_home"
+        "--regression=ir=5.0"
+        "--save-summary"
+    )
+
+    # Parse `cargo_arg0 cargo_arg1 -- iai_arg0 iai_arg1` syntax
+    parsing_iai_args=0
+    while [ "$#" -gt 0 ]; do
+        if [ "$parsing_iai_args" == "1" ]; then
+            iai_args+=("$1")
+        elif [ "$1" == "--" ]; then
+            parsing_iai_args=1
+        else
+            cargo_args+=("$1")
+        fi
+
+        shift
+    done
+
+    # Run iai-callgrind benchmarks
+    cargo bench "${cargo_args[@]}" -- "${iai_args[@]}"
+
+    # NB: iai-callgrind should exit on error but does not, so we inspect the sumary
+    # for errors. See  https://github.com/iai-callgrind/iai-callgrind/issues/337
+    ./ci/ci-util.py check-regressions --home "$iai_home" || true
+}
+
+# Run once with softfloats, once with arch instructions enabled
+run_icount_benchmarks --features force-soft-floats -- --save-baseline=softfloat
+run_icount_benchmarks -- --save-baseline=hardfloat
+
+# Name and tar the new baseline
+name="baseline-icount-$(date -u +'%Y%m%d%H%M')-${GITHUB_SHA:0:12}"
+echo "BASELINE_NAME=$name" >>"$GITHUB_ENV"
+tar cJf "$name.tar.xz" "$iai_home"