[llvm] [CI] Disable Flang from pre-commit tests when Flang files are not touched on Windows Only (PR #93729)

[Mehdi Amini via llvm-commits]

https://github.com/joker-eph created https://github.com/llvm/llvm-project/pull/93729

Flang triggers some OOM on Windows CI right now. This is disruptive to MLIR and LLVM changes that don't touch Flang, as such we disable building Flang on Windows only for these PR that don't touch flang. The testing on Linux is unchanged, and the post-merge Windows testing is still fully covering here.

>From 6ffb85173adbe43e33ea7bd062f28fe0e5bdc01d Mon Sep 17 00:00:00 2001
From: Mehdi Amini <joker.eph at gmail.com>
Date: Wed, 29 May 2024 13:00:27 -0700
Subject: [PATCH] [CI] Disable Flang from pre-commit tests when Flang files are
 not touched on Windows Only

Flang triggers some OOM on Windows CI right now. This is disruptive
to MLIR and LLVM changes that don't touch Flang, as such we disable
building Flang on Windows only for these PR that don't touch flang.
The testing on Linux is unchanged, and the post-merge Windows testing
is still fully covering here.
---
 .ci/generate-buildkite-pipeline-premerge | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/.ci/generate-buildkite-pipeline-premerge b/.ci/generate-buildkite-pipeline-premerge
index 3ed5eb96eceb5..bb7d2117e277f 100755
--- a/.ci/generate-buildkite-pipeline-premerge
+++ b/.ci/generate-buildkite-pipeline-premerge
@@ -53,7 +53,10 @@ echo "Directories modified:" >&2
 echo "$modified_dirs" >&2
 
 function compute-projects-to-test() {
+  isForWindows=$1
+  shift
   projects=${@}
+  echo "isForWindows : $isForWindows ; projects: $projects " >&2
   for project in ${projects}; do
     echo "${project}"
     case ${project} in
@@ -63,9 +66,13 @@ function compute-projects-to-test() {
       done
     ;;
     llvm)
-      for p in bolt clang clang-tools-extra flang lld lldb mlir polly; do
+      for p in bolt clang clang-tools-extra lld lldb mlir polly; do
         echo $p
       done
+      # Flang is not stable in Windows CI at the moment
+      if [[ $isForWindows == 0 ]]; then
+        echo flang
+      fi
     ;;
     clang)
       for p in clang-tools-extra compiler-rt lldb cross-project-tests; do
@@ -76,7 +83,10 @@ function compute-projects-to-test() {
       echo libc
     ;;
     mlir)
-      echo flang
+      # Flang is not stable in Windows CI at the moment
+      if [[ $isForWindows == 0 ]]; then
+        echo flang
+      fi
     ;;
     *)
       # Nothing to do
@@ -241,7 +251,7 @@ fi
 all_projects="bolt clang clang-tools-extra compiler-rt cross-project-tests flang libc libclc lld lldb llvm mlir openmp polly pstl"
 modified_projects="$(keep-modified-projects ${all_projects})"
 
-linux_projects_to_test=$(exclude-linux $(compute-projects-to-test ${modified_projects}))
+linux_projects_to_test=$(exclude-linux $(compute-projects-to-test 0 ${modified_projects}))
 linux_check_targets=$(check-targets ${linux_projects_to_test} | sort | uniq)
 linux_projects=$(add-dependencies ${linux_projects_to_test} | sort | uniq)
 
@@ -249,7 +259,7 @@ linux_runtimes_to_test=$(compute-runtimes-to-test ${linux_projects_to_test})
 linux_runtime_check_targets=$(check-targets ${linux_runtimes_to_test} | sort | uniq)
 linux_runtimes=$(echo ${linux_runtimes_to_test} | sort | uniq)
 
-windows_projects_to_test=$(exclude-windows $(compute-projects-to-test ${modified_projects}))
+windows_projects_to_test=$(exclude-windows $(compute-projects-to-test 1 ${modified_projects}))
 windows_check_targets=$(check-targets ${windows_projects_to_test} | sort | uniq)
 windows_projects=$(add-dependencies ${windows_projects_to_test} | sort | uniq)