Don't disable codegen tests in PR CI

src/ci/docker/scripts/x86_64-gnu-llvm.sh

@@ -4,13 +4,7 @@ set -ex
 
 # Only run the stage 1 tests on merges, not on PR CI jobs.
 if [[ -z "${PR_CI_JOB}" ]]; then
-    # When running gcc backend tests, we need to install `libgccjit` and to not run llvm codegen
-    # tests as it will fail them.
-    if [[ "${ENABLE_GCC_CODEGEN}" == "1" ]]; then
-        ../x.py --stage 1 test --skip src/tools/tidy --skip tests/codegen
-    else
-        ../x.py --stage 1 test --skip src/tools/tidy
-    fi
+    ../x.py --stage 1 test --skip src/tools/tidy
 
     # Run the `mir-opt` tests again but this time for a 32-bit target.
     # This enforces that tests using `// EMIT_MIR_FOR_EACH_BIT_WIDTH` have
@@ -29,14 +23,8 @@ if [[ -z "${PR_CI_JOB}" ]]; then
         --rustc-args "--cfg feature=\"optimize_for_size\""
 fi
 
-# When running gcc backend tests, we need to install `libgccjit` and to not run llvm codegen
-# tests as it will fail them.
 # NOTE: intentionally uses all of `x.py`, `x`, and `x.ps1` to make sure they all work on Linux.
-if [[ "${ENABLE_GCC_CODEGEN}" == "1" ]]; then
-    ../x.py --stage 2 test --skip src/tools/tidy --skip tests/codegen
-else
-    ../x.py --stage 2 test --skip src/tools/tidy
-fi
+../x.py --stage 2 test --skip src/tools/tidy
 
 # Run the `mir-opt` tests again but this time for a 32-bit target.
 # This enforces that tests using `// EMIT_MIR_FOR_EACH_BIT_WIDTH` have