[llvm-reduce] Split operands-skip.ll into serial and parallel parts

This fixes a test failure when building with LLVM_ENABLE_THREADS=OFF.

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D130707

Author: DavidSpickett

llvm/test/tools/llvm-reduce/operands-skip-parallel.ll

@@ -0,0 +1,8 @@
+; This reuses llvm/test/tools/llvm-reduce/operands-skip.ll
+; REQUIRES: thread_support
+
+; RUN: llvm-reduce -j 2 %S/operands-skip.ll -o %t.1 --delta-passes=operands-skip --test FileCheck --test-arg %S/operands-skip.ll --test-arg --match-full-lines --test-arg --check-prefix=INTERESTING --test-arg --input-file
+; RUN: FileCheck %S/operands-skip.ll --input-file %t.1 --check-prefixes=REDUCED
+
+; RUN: llvm-reduce -j 4 %S/operands-skip.ll -o %t.2 --delta-passes=operands-skip --test FileCheck --test-arg %S/operands-skip.ll --test-arg --match-full-lines --test-arg --check-prefix=INTERESTING --test-arg --input-file
+; RUN: FileCheck %S/operands-skip.ll --input-file %t.2 --check-prefixes=REDUCED

llvm/test/tools/llvm-reduce/operands-skip.ll

@@ -1,13 +1,6 @@
 ; RUN: llvm-reduce %s -o %t --delta-passes=operands-skip --test FileCheck --test-arg %s --test-arg --match-full-lines --test-arg --check-prefix=INTERESTING --test-arg --input-file
 ; RUN: FileCheck %s --input-file %t --check-prefixes=REDUCED
 
-; RUN: llvm-reduce -j 2 %s -o %t.1 --delta-passes=operands-skip --test FileCheck --test-arg %s --test-arg --match-full-lines --test-arg --check-prefix=INTERESTING --test-arg --input-file
-; RUN: FileCheck %s --input-file %t.1 --check-prefixes=REDUCED
-
-; RUN: llvm-reduce -j 4 %s -o %t.2 --delta-passes=operands-skip --test FileCheck --test-arg %s --test-arg --match-full-lines --test-arg --check-prefix=INTERESTING --test-arg --input-file
-; RUN: FileCheck %s --input-file %t.2 --check-prefixes=REDUCED
-
-
 ; INTERESTING: store i32 43, i32* {{(%imm|%indirect)}}, align 4
 ; REDUCED:     store i32 43, i32* %imm, align 4