[llvm] Reapply "[CI] Save sccache logs (#155444)" (PR #155520)

[Aiden Grossman via llvm-commits]

https://github.com/boomanaiden154 created https://github.com/llvm/llvm-project/pull/155520

This reverts commit b90f4ff3020c6fe018ec22b22a7faa5541ed5372.

Relands the change after making the relevant fixes (not missing the `artifacts` directory).

>From 4e46f27ebdd1f3ecf67aa146dc928f2cf9c839f5 Mon Sep 17 00:00:00 2001
From: Aiden Grossman <aidengrossman at google.com>
Date: Tue, 26 Aug 2025 23:23:51 +0000
Subject: [PATCH] Reapply "[CI] Save sccache logs (#155444)"

This reverts commit b90f4ff3020c6fe018ec22b22a7faa5541ed5372.
---
 .github/workflows/premerge.yaml | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/premerge.yaml b/.github/workflows/premerge.yaml
index 9d925517a7211..ce4b8488014e2 100644
--- a/.github/workflows/premerge.yaml
+++ b/.github/workflows/premerge.yaml
@@ -65,7 +65,8 @@ jobs:
           # several test suites in a row and discard statistics that we want
           # to save in the end.
           export SCCACHE_IDLE_TIMEOUT=0
-          sccache --start-server
+          mkdir artifacts
+          SCCACHE_LOG=info SCCACHE_ERROR_LOG=artifacts/sccache.log sccache --start-server
 
           ./.ci/monolithic-linux.sh "${projects_to_build}" "${project_check_targets}" "${runtimes_to_build}" "${runtimes_check_targets}" "${runtimes_check_targets_needs_reconfig}" "${enable_cir}"
       - name: Upload Artifacts
@@ -117,7 +118,7 @@ jobs:
           call C:\\BuildTools\\Common7\\Tools\\VsDevCmd.bat -arch=amd64 -host_arch=amd64
           # See the comments above in the Linux job for why we define each of
           # these environment variables.
-          bash -c "export SCCACHE_GCS_BUCKET=$CACHE_GCS_BUCKET; export SCCACHE_GCS_RW_MODE=READ_WRITE; export SCCACHE_IDLE_TIMEOUT=0; sccache --start-server; .ci/monolithic-windows.sh \"${{ steps.vars.outputs.windows-projects }}\" \"${{ steps.vars.outputs.windows-check-targets }}\""
+          bash -c "export SCCACHE_GCS_BUCKET=$CACHE_GCS_BUCKET; export SCCACHE_GCS_RW_MODE=READ_WRITE; export SCCACHE_IDLE_TIMEOUT=0; mkdir artifacts; SCCACHE_LOG=info SCCACHE_ERROR_LOG=artifacts/sccache.log sccache --start-server; .ci/monolithic-windows.sh \"${{ steps.vars.outputs.windows-projects }}\" \"${{ steps.vars.outputs.windows-check-targets }}\""
       - name: Upload Artifacts
         # In some cases, Github will fail to upload the artifact. We want to
         # continue anyways as a failed artifact upload is an infra failure, not