[AMDGPU] AMDGPULateCodeGenPrepare: legacy-pm replace setPreservesAll() with setPreservesCFG()

Author: J-MR-T

llvm/lib/Target/AMDGPU/AMDGPULateCodeGenPrepare.cpp

@@ -546,7 +546,9 @@ class AMDGPULateCodeGenPrepareLegacy : public FunctionPass {
     AU.addRequired<TargetPassConfig>();
     AU.addRequired<AssumptionCacheTracker>();
     AU.addRequired<UniformityInfoWrapperPass>();
-    AU.setPreservesAll();
+    // makes changes that can invalidate Uniformity Analysis,
+    // so don't preserveAll here (see new PM version above)
+    AU.setPreservesCFG();
   }
 
   bool runOnFunction(Function &F) override;

llvm/test/CodeGen/AMDGPU/llc-pipeline.ll

@@ -255,6 +255,7 @@
 ; GCN-O1-NEXT:        Uniformity Analysis
 ; GCN-O1-NEXT:        AMDGPU IR late optimizations
 ; GCN-O1-NEXT:        Post-Dominator Tree Construction
+; GCN-O1-NEXT:        Uniformity Analysis
 ; GCN-O1-NEXT:        Unify divergent function exit nodes
 ; GCN-O1-NEXT:        Dominator Tree Construction
 ; GCN-O1-NEXT:        Cycle Info Analysis
@@ -557,6 +558,7 @@
 ; GCN-O1-OPTS-NEXT:        Uniformity Analysis
 ; GCN-O1-OPTS-NEXT:        AMDGPU IR late optimizations
 ; GCN-O1-OPTS-NEXT:        Post-Dominator Tree Construction
+; GCN-O1-OPTS-NEXT:        Uniformity Analysis
 ; GCN-O1-OPTS-NEXT:        Unify divergent function exit nodes
 ; GCN-O1-OPTS-NEXT:        Dominator Tree Construction
 ; GCN-O1-OPTS-NEXT:        Cycle Info Analysis
@@ -871,6 +873,7 @@
 ; GCN-O2-NEXT:        Uniformity Analysis
 ; GCN-O2-NEXT:        AMDGPU IR late optimizations
 ; GCN-O2-NEXT:        Post-Dominator Tree Construction
+; GCN-O2-NEXT:        Uniformity Analysis
 ; GCN-O2-NEXT:        Unify divergent function exit nodes
 ; GCN-O2-NEXT:        Dominator Tree Construction
 ; GCN-O2-NEXT:        Cycle Info Analysis
@@ -1200,6 +1203,7 @@
 ; GCN-O3-NEXT:        Uniformity Analysis
 ; GCN-O3-NEXT:        AMDGPU IR late optimizations
 ; GCN-O3-NEXT:        Post-Dominator Tree Construction
+; GCN-O3-NEXT:        Uniformity Analysis
 ; GCN-O3-NEXT:        Unify divergent function exit nodes
 ; GCN-O3-NEXT:        Dominator Tree Construction
 ; GCN-O3-NEXT:        Cycle Info Analysis