[AMDGPU] Enable Atomic Optimizer and Default to Iterative Scan Strategy.

The D147408 implemented new Iterative approach for scan computations
and  added new flag `amdgpu-atomic-optimizer-strategy` which is
defaulted to DPP.

The changeset GPUOpen-Drivers/llpc#2506
adapts to the new changes in LLPC.

This patch enables atomic optimizer pass and selects Iterative
approach for scan computations by default for compute pipeline.

Reviewed By: foad

Differential Revision: https://reviews.llvm.org/D152649

llvm/lib/Target/AMDGPU/AMDGPUTargetMachine.cpp

@@ -278,12 +278,12 @@ static cl::opt<bool> OptVGPRLiveRange(
 static cl::opt<bool>
     EnableAtomicOptimizations("amdgpu-atomic-optimizations",
                               cl::desc("Enable atomic optimizations"),
-                              cl::init(false), cl::Hidden);
+                              cl::init(true), cl::Hidden);
 
 static cl::opt<ScanOptions> AMDGPUAtomicOptimizerStrategy(
     "amdgpu-atomic-optimizer-strategy",
     cl::desc("Select DPP or Iterative strategy for scan"),
-    cl::init(ScanOptions::DPP),
+    cl::init(ScanOptions::Iterative),
     cl::values(clEnumValN(ScanOptions::DPP, "DPP",
                           "Use DPP operations for scan"),
                clEnumValN(ScanOptions::Iterative, "Iterative",

llvm/test/CodeGen/AMDGPU/GlobalISel/mubuf-global.ll

@@ -1,6 +1,6 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
-; RUN: llc -global-isel -mtriple=amdgcn-mesa-mesa3d -mcpu=tahiti < %s | FileCheck -check-prefix=GFX6 %s
-; RUN: llc -global-isel -mtriple=amdgcn-mesa-mesa3d -mcpu=hawaii < %s | FileCheck -check-prefix=GFX7 %s
+; RUN: llc -global-isel -mtriple=amdgcn-mesa-mesa3d -mcpu=tahiti -amdgpu-atomic-optimizations=false < %s | FileCheck -check-prefix=GFX6 %s
+; RUN: llc -global-isel -mtriple=amdgcn-mesa-mesa3d -mcpu=hawaii -amdgpu-atomic-optimizations=false < %s | FileCheck -check-prefix=GFX7 %s
 
 ; Test end to end matching of addressing modes when MUBUF is used for
 ; global memory.

llvm/test/CodeGen/AMDGPU/atomic_optimizations_pixelshader.ll

@@ -1,11 +1,11 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
-; RUN: llc -mtriple=amdgcn-- -amdgpu-atomic-optimizations=true -verify-machineinstrs -simplifycfg-require-and-preserve-domtree=1 < %s | FileCheck -enable-var-scope -check-prefixes=GFX7 %s
-; RUN: llc  -mtriple=amdgcn-- -mcpu=tonga -mattr=-flat-for-global -amdgpu-atomic-optimizations=true -verify-machineinstrs -simplifycfg-require-and-preserve-domtree=1 < %s | FileCheck -enable-var-scope -check-prefixes=GFX89,GFX8 %s
-; RUN: llc -mtriple=amdgcn-- -mcpu=gfx900 -mattr=-flat-for-global -amdgpu-atomic-optimizations=true -verify-machineinstrs -simplifycfg-require-and-preserve-domtree=1 < %s | FileCheck -enable-var-scope -check-prefixes=GFX89,GFX9 %s
-; RUN: llc -mtriple=amdgcn-- -mcpu=gfx1010 -mattr=-wavefrontsize32,+wavefrontsize64 -mattr=-flat-for-global -amdgpu-atomic-optimizations=true -verify-machineinstrs -simplifycfg-require-and-preserve-domtree=1 < %s | FileCheck -enable-var-scope -check-prefixes=GFX1064 %s
-; RUN: llc -mtriple=amdgcn-- -mcpu=gfx1010 -mattr=+wavefrontsize32,-wavefrontsize64 -mattr=-flat-for-global -amdgpu-atomic-optimizations=true -verify-machineinstrs -simplifycfg-require-and-preserve-domtree=1 < %s | FileCheck -enable-var-scope -check-prefixes=GFX1032 %s
-; RUN: llc -mtriple=amdgcn-- -mcpu=gfx1100 -mattr=-wavefrontsize32,+wavefrontsize64 -mattr=-flat-for-global -amdgpu-atomic-optimizations=true -verify-machineinstrs -simplifycfg-require-and-preserve-domtree=1 < %s | FileCheck -enable-var-scope -check-prefixes=GFX1164 %s
-; RUN: llc -mtriple=amdgcn-- -mcpu=gfx1100 -mattr=+wavefrontsize32,-wavefrontsize64 -mattr=-flat-for-global -amdgpu-atomic-optimizations=true -verify-machineinstrs -simplifycfg-require-and-preserve-domtree=1 < %s | FileCheck -enable-var-scope -check-prefixes=GFX1132 %s
+; RUN: llc -mtriple=amdgcn-- -amdgpu-atomic-optimizations=true -amdgpu-atomic-optimizer-strategy=DPP -verify-machineinstrs -simplifycfg-require-and-preserve-domtree=1 < %s | FileCheck -enable-var-scope -check-prefixes=GFX7 %s
+; RUN: llc  -mtriple=amdgcn-- -mcpu=tonga -mattr=-flat-for-global -amdgpu-atomic-optimizations=true -amdgpu-atomic-optimizer-strategy=DPP -verify-machineinstrs -simplifycfg-require-and-preserve-domtree=1 < %s | FileCheck -enable-var-scope -check-prefixes=GFX89,GFX8 %s
+; RUN: llc -mtriple=amdgcn-- -mcpu=gfx900 -mattr=-flat-for-global -amdgpu-atomic-optimizations=true -amdgpu-atomic-optimizer-strategy=DPP -verify-machineinstrs -simplifycfg-require-and-preserve-domtree=1 < %s | FileCheck -enable-var-scope -check-prefixes=GFX89,GFX9 %s
+; RUN: llc -mtriple=amdgcn-- -mcpu=gfx1010 -mattr=-wavefrontsize32,+wavefrontsize64 -mattr=-flat-for-global -amdgpu-atomic-optimizations=true -amdgpu-atomic-optimizer-strategy=DPP -verify-machineinstrs -simplifycfg-require-and-preserve-domtree=1 < %s | FileCheck -enable-var-scope -check-prefixes=GFX1064 %s
+; RUN: llc -mtriple=amdgcn-- -mcpu=gfx1010 -mattr=+wavefrontsize32,-wavefrontsize64 -mattr=-flat-for-global -amdgpu-atomic-optimizations=true -amdgpu-atomic-optimizer-strategy=DPP -verify-machineinstrs -simplifycfg-require-and-preserve-domtree=1 < %s | FileCheck -enable-var-scope -check-prefixes=GFX1032 %s
+; RUN: llc -mtriple=amdgcn-- -mcpu=gfx1100 -mattr=-wavefrontsize32,+wavefrontsize64 -mattr=-flat-for-global -amdgpu-atomic-optimizations=true -amdgpu-atomic-optimizer-strategy=DPP -verify-machineinstrs -simplifycfg-require-and-preserve-domtree=1 < %s | FileCheck -enable-var-scope -check-prefixes=GFX1164 %s
+; RUN: llc -mtriple=amdgcn-- -mcpu=gfx1100 -mattr=+wavefrontsize32,-wavefrontsize64 -mattr=-flat-for-global -amdgpu-atomic-optimizations=true -amdgpu-atomic-optimizer-strategy=DPP -verify-machineinstrs -simplifycfg-require-and-preserve-domtree=1 < %s | FileCheck -enable-var-scope -check-prefixes=GFX1132 %s
 
 declare i1 @llvm.amdgcn.wqm.vote(i1)
 declare i32 @llvm.amdgcn.raw.ptr.buffer.atomic.add(i32, ptr addrspace(8), i32, i32, i32 immarg)

llvm/test/CodeGen/AMDGPU/buffer-intrinsics-mmo-offsets.ll

@@ -1,5 +1,5 @@
 ; NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
-; RUN: llc -march=amdgcn -mcpu=gfx908 -verify-machineinstrs -stop-after=amdgpu-isel -o - %s | FileCheck -check-prefix=GCN %s
+; RUN: llc -march=amdgcn -mcpu=gfx908 -verify-machineinstrs -amdgpu-atomic-optimizations=false -stop-after=amdgpu-isel -o - %s | FileCheck -check-prefix=GCN %s
 
 define amdgpu_cs void @mmo_offsets0(ptr addrspace(6) inreg noalias align(16) dereferenceable(18446744073709551615) %arg0, i32 %arg1) {
   ; GCN-LABEL: name: mmo_offsets0

llvm/test/CodeGen/AMDGPU/dag-divergence-atomic.ll

@@ -1,5 +1,5 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
-; RUN: llc -march=amdgcn -mcpu=gfx90a -o - %s | FileCheck %s
+; RUN: llc -march=amdgcn -mcpu=gfx90a -amdgpu-atomic-optimizations=false -o - %s | FileCheck %s
 
 %S = type <{ float, double }>
 

llvm/test/CodeGen/AMDGPU/gds-allocation.ll

@@ -1,5 +1,5 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
-; RUN: llc -mtriple=amdgcn-amd-amdpal -mcpu=gfx900 -verify-machineinstrs < %s | FileCheck -check-prefix=GCN %s
+; RUN: llc -mtriple=amdgcn-amd-amdpal -mcpu=gfx900 -amdgpu-atomic-optimizations=false -verify-machineinstrs < %s | FileCheck -check-prefix=GCN %s
 
 @gds0 = internal addrspace(2) global [4 x i32] undef, align 4
 @lds0 = internal addrspace(3) global [4 x i32] undef, align 128

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

@@ -251,11 +251,14 @@
 ; GCN-O1-NEXT:        Cycle Info Analysis
 ; GCN-O1-NEXT:        Uniformity Analysis
 ; GCN-O1-NEXT:        AMDGPU IR late optimizations
+; GCN-O1-NEXT:        AMDGPU atomic optimizations
 ; GCN-O1-NEXT:        Basic Alias Analysis (stateless AA impl)
 ; GCN-O1-NEXT:        Function Alias Analysis Results
 ; GCN-O1-NEXT:        Natural Loop Information
 ; GCN-O1-NEXT:        Code sinking
 ; GCN-O1-NEXT:        Post-Dominator Tree Construction
+; GCN-O1-NEXT:        Cycle Info Analysis
+; GCN-O1-NEXT:        Uniformity Analysis
 ; GCN-O1-NEXT:        Unify divergent function exit nodes
 ; GCN-O1-NEXT:        Lazy Value Information Analysis
 ; GCN-O1-NEXT:        Lower SwitchInst's to branches
@@ -541,11 +544,14 @@
 ; GCN-O1-OPTS-NEXT:        Cycle Info Analysis
 ; GCN-O1-OPTS-NEXT:        Uniformity Analysis
 ; GCN-O1-OPTS-NEXT:        AMDGPU IR late optimizations
+; GCN-O1-OPTS-NEXT:        AMDGPU atomic optimizations
 ; GCN-O1-OPTS-NEXT:        Basic Alias Analysis (stateless AA impl)
 ; GCN-O1-OPTS-NEXT:        Function Alias Analysis Results
 ; GCN-O1-OPTS-NEXT:        Natural Loop Information
 ; GCN-O1-OPTS-NEXT:        Code sinking
 ; GCN-O1-OPTS-NEXT:        Post-Dominator Tree Construction
+; GCN-O1-OPTS-NEXT:        Cycle Info Analysis
+; GCN-O1-OPTS-NEXT:        Uniformity Analysis
 ; GCN-O1-OPTS-NEXT:        Unify divergent function exit nodes
 ; GCN-O1-OPTS-NEXT:        Lazy Value Information Analysis
 ; GCN-O1-OPTS-NEXT:        Lower SwitchInst's to branches
@@ -847,11 +853,14 @@
 ; GCN-O2-NEXT:        Cycle Info Analysis
 ; GCN-O2-NEXT:        Uniformity Analysis
 ; GCN-O2-NEXT:        AMDGPU IR late optimizations
+; GCN-O2-NEXT:        AMDGPU atomic optimizations
 ; GCN-O2-NEXT:        Basic Alias Analysis (stateless AA impl)
 ; GCN-O2-NEXT:        Function Alias Analysis Results
 ; GCN-O2-NEXT:        Natural Loop Information
 ; GCN-O2-NEXT:        Code sinking
 ; GCN-O2-NEXT:        Post-Dominator Tree Construction
+; GCN-O2-NEXT:        Cycle Info Analysis
+; GCN-O2-NEXT:        Uniformity Analysis
 ; GCN-O2-NEXT:        Unify divergent function exit nodes
 ; GCN-O2-NEXT:        Lazy Value Information Analysis
 ; GCN-O2-NEXT:        Lower SwitchInst's to branches
@@ -1168,11 +1177,14 @@
 ; GCN-O3-NEXT:        Cycle Info Analysis
 ; GCN-O3-NEXT:        Uniformity Analysis
 ; GCN-O3-NEXT:        AMDGPU IR late optimizations
+; GCN-O3-NEXT:        AMDGPU atomic optimizations
 ; GCN-O3-NEXT:        Basic Alias Analysis (stateless AA impl)
 ; GCN-O3-NEXT:        Function Alias Analysis Results
 ; GCN-O3-NEXT:        Natural Loop Information
 ; GCN-O3-NEXT:        Code sinking
 ; GCN-O3-NEXT:        Post-Dominator Tree Construction
+; GCN-O3-NEXT:        Cycle Info Analysis
+; GCN-O3-NEXT:        Uniformity Analysis
 ; GCN-O3-NEXT:        Unify divergent function exit nodes
 ; GCN-O3-NEXT:        Lazy Value Information Analysis
 ; GCN-O3-NEXT:        Lower SwitchInst's to branches

llvm/test/CodeGen/AMDGPU/noclobber-barrier.ll

@@ -1,6 +1,6 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
 ; RUN: opt -march=amdgcn -mcpu=gfx900 -amdgpu-aa -amdgpu-aa-wrapper -amdgpu-annotate-uniform -S --amdgpu-lower-module-lds-strategy=module < %s | FileCheck %s
-; RUN: llc -march=amdgcn -mcpu=gfx900 -verify-machineinstrs --amdgpu-lower-module-lds-strategy=module < %s | FileCheck -check-prefix=GCN %s
+; RUN: llc -march=amdgcn -mcpu=gfx900 -verify-machineinstrs --amdgpu-lower-module-lds-strategy=module -amdgpu-atomic-optimizations=false < %s | FileCheck -check-prefix=GCN %s
 
 ; Check that barrier or fence in between of loads is not considered a clobber
 ; for the purpose of converting vector loads into scalar.

llvm/test/CodeGen/AMDGPU/should-not-hoist-set-inactive.ll

@@ -1,5 +1,5 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 2
-; RUN: llc -march=amdgcn -mcpu=gfx1010 -verify-machineinstrs < %s | FileCheck %s -check-prefix=GCN
+; RUN: llc -march=amdgcn -mcpu=gfx1010 -amdgpu-atomic-optimizations=false -verify-machineinstrs < %s | FileCheck %s -check-prefix=GCN
 
 define amdgpu_cs void @should_not_hoist_set_inactive(<4 x i32> inreg %i14, i32 inreg %v, i32 %lane, i32 %f, i32 %f2) #0 {
 ; GCN-LABEL: should_not_hoist_set_inactive: