[flang-commits] [flang] [clang] Revert "[flang] Enable alias tags pass by default (#73111)" (PR #73821)
Tom Eccles via flang-commits
flang-commits at lists.llvm.org
Wed Nov 29 09:07:10 PST 2023
https://github.com/tblah created https://github.com/llvm/llvm-project/pull/73821
This reverts commit caba0314cf631a3ba3e982cbcdc455224046c7a8.
Serious performance regressions were reported by @vzakhari https://github.com/llvm/llvm-project/issues/58303#issuecomment-1830754173
Fixing this doesn't look quick so I will revert for now.
>From 3ae4f09419369223244a64af9de9dc02c0c3acd9 Mon Sep 17 00:00:00 2001
From: Tom Eccles <tom.eccles at arm.com>
Date: Wed, 29 Nov 2023 17:04:40 +0000
Subject: [PATCH] Revert "[flang] Enable alias tags pass by default (#73111)"
This reverts commit caba0314cf631a3ba3e982cbcdc455224046c7a8.
Serious performance regressions were reported by @vzakhari
https://github.com/llvm/llvm-project/issues/58303#issuecomment-1830754173
Fixing this doesn't look quick so I will revert for now.
---
clang/lib/Driver/ToolChains/Flang.cpp | 20 --------------------
flang/include/flang/Tools/CLOptions.inc | 6 +++---
flang/lib/Frontend/CompilerInvocation.cpp | 10 ++++------
flang/test/Driver/falias-analysis.f90 | 16 +---------------
flang/test/Driver/mlir-pass-pipeline.f90 | 2 --
flang/test/Driver/optimization-remark.f90 | 22 +++++++++++++---------
flang/test/Fir/basic-program.fir | 4 ----
flang/tools/tco/tco.cpp | 1 -
8 files changed, 21 insertions(+), 60 deletions(-)
diff --git a/clang/lib/Driver/ToolChains/Flang.cpp b/clang/lib/Driver/ToolChains/Flang.cpp
index 86e1c57e485685e..01f07b9228256cf 100644
--- a/clang/lib/Driver/ToolChains/Flang.cpp
+++ b/clang/lib/Driver/ToolChains/Flang.cpp
@@ -142,26 +142,6 @@ void Flang::addCodegenOptions(const ArgList &Args,
if (shouldLoopVersion(Args))
CmdArgs.push_back("-fversion-loops-for-stride");
- Arg *aliasAnalysis = Args.getLastArg(options::OPT_falias_analysis,
- options::OPT_fno_alias_analysis);
- // only pass on the argument if it does not match that implied by the
- // optimization level: so if optimization is requested, only forward
- // -fno-alias-analysis. If optimization is not requested, only forward
- // -falias-analysis.
- Arg *optLevel =
- Args.getLastArg(options::OPT_Ofast, options::OPT_O, options::OPT_O4);
- if (aliasAnalysis) {
- bool faliasAnalysis =
- aliasAnalysis->getOption().matches(options::OPT_falias_analysis);
- if (optLevel && !faliasAnalysis) {
- CmdArgs.push_back("-fno-alias-analysis");
- } else {
- if (faliasAnalysis)
- // requested alias analysis but no optimization enabled
- CmdArgs.push_back("-falias-analysis");
- }
- }
-
Args.addAllArgs(CmdArgs, {options::OPT_flang_experimental_hlfir,
options::OPT_flang_deprecated_no_hlfir,
options::OPT_flang_experimental_polymorphism,
diff --git a/flang/include/flang/Tools/CLOptions.inc b/flang/include/flang/Tools/CLOptions.inc
index d3e4dc6cd4a243e..c452c023b4a80ce 100644
--- a/flang/include/flang/Tools/CLOptions.inc
+++ b/flang/include/flang/Tools/CLOptions.inc
@@ -158,10 +158,10 @@ inline void addDebugFoundationPass(mlir::PassManager &pm) {
}
inline void addFIRToLLVMPass(
- mlir::PassManager &pm, const MLIRToLLVMPassPipelineConfig &config) {
+ mlir::PassManager &pm, llvm::OptimizationLevel optLevel = defaultOptLevel) {
fir::FIRToLLVMPassOptions options;
options.ignoreMissingTypeDescriptors = ignoreMissingTypeDescriptors;
- options.applyTBAA = config.AliasAnalysis;
+ options.applyTBAA = optLevel.isOptimizingForSpeed();
options.forceUnifiedTBAATree = useOldAliasTags;
addPassConditionally(pm, disableFirToLlvmIr,
[&]() { return fir::createFIRToLLVMPass(options); });
@@ -311,7 +311,7 @@ inline void createDefaultFIRCodeGenPassPipeline(
if (config.VScaleMin != 0)
pm.addPass(fir::createVScaleAttrPass({config.VScaleMin, config.VScaleMax}));
- fir::addFIRToLLVMPass(pm, config);
+ fir::addFIRToLLVMPass(pm, config.OptLevel);
}
/// Create a pass pipeline for lowering from MLIR to LLVM IR
diff --git a/flang/lib/Frontend/CompilerInvocation.cpp b/flang/lib/Frontend/CompilerInvocation.cpp
index 1c09ae9c281eb47..cb4f2d6a6225205 100644
--- a/flang/lib/Frontend/CompilerInvocation.cpp
+++ b/flang/lib/Frontend/CompilerInvocation.cpp
@@ -242,12 +242,10 @@ static void parseCodeGenArgs(Fortran::frontend::CodeGenOptions &opts,
clang::driver::options::OPT_fno_loop_versioning, false))
opts.LoopVersioning = 1;
- opts.AliasAnalysis = opts.OptimizationLevel > 0;
- if (auto *arg =
- args.getLastArg(clang::driver::options::OPT_falias_analysis,
- clang::driver::options::OPT_fno_alias_analysis))
- opts.AliasAnalysis =
- arg->getOption().matches(clang::driver::options::OPT_falias_analysis);
+ opts.AliasAnalysis =
+ args.hasFlag(clang::driver::options::OPT_falias_analysis,
+ clang::driver::options::OPT_fno_alias_analysis,
+ /*default=*/false);
for (auto *a : args.filtered(clang::driver::options::OPT_fpass_plugin_EQ))
opts.LLVMPassPlugins.push_back(a->getValue());
diff --git a/flang/test/Driver/falias-analysis.f90 b/flang/test/Driver/falias-analysis.f90
index 3bd389c33dbc578..f2c5dbde6d2c878 100644
--- a/flang/test/Driver/falias-analysis.f90
+++ b/flang/test/Driver/falias-analysis.f90
@@ -2,26 +2,12 @@
! See flang/test/Fir/tbaa-codegen.fir for a test that the output is correct
! RUN: %flang -c -emit-llvm -falias-analysis %s -o - | llvm-dis | FileCheck %s --check-prefix=CHECK-AA --check-prefix=CHECK-ALL
-! RUN: %flang -c -emit-llvm -Ofast %s -o - | llvm-dis | FileCheck %s --check-prefix=CHECK-AA --check-prefix=CHECK-ALL
-! RUN: %flang -c -emit-llvm -O3 %s -o - | llvm-dis | FileCheck %s --check-prefix=CHECK-AA --check-prefix=CHECK-ALL
-! RUN: %flang -c -emit-llvm -O2 %s -o - | llvm-dis | FileCheck %s --check-prefix=CHECK-AA --check-prefix=CHECK-ALL
-! RUN: %flang -c -emit-llvm -O1 %s -o - | llvm-dis | FileCheck %s --check-prefix=CHECK-AA --check-prefix=CHECK-ALL
-
-! RUN: %flang -c -emit-llvm -O0 %s -o - | llvm-dis | FileCheck %s --check-prefix=CHECK-NOAA --check-prefix=CHECK-ALL
-! RUN: %flang -c -emit-llvm -Ofast -fno-alias-analysis %s -o - | llvm-dis | FileCheck %s --check-prefix=CHECK-NOAA --check-prefix=CHECK-ALL
-! RUN: %flang -c -emit-llvm -fno-alias-analysis -Ofast %s -o - | llvm-dis | FileCheck %s --check-prefix=CHECK-NOAA --check-prefix=CHECK-ALL
-! RUN: %flang -c -emit-llvm %s -o - | llvm-dis | FileCheck %s --check-prefix=CHECK-NOAA --check-prefix=CHECK-ALL
! RUN: %flang -c -emit-llvm -falias-analysis -fno-alias-analysis %s -o - | llvm-dis | FileCheck %s --check-prefix=CHECK-NOAA --check-prefix=CHECK-ALL
+! RUN: %flang -c -emit-llvm %s -o - | llvm-dis | FileCheck %s --check-prefix=CHECK-NOAA --check-prefix=CHECK-ALL
! RUN: %flang -fc1 -emit-llvm -falias-analysis %s -o - | FileCheck %s --check-prefix=CHECK-AA --check-prefix=CHECK-ALL
-! RUN: %flang -fc1 -emit-llvm -O3 %s -o - | FileCheck %s --check-prefix=CHECK-AA --check-prefix=CHECK-ALL
-! RUN: %flang -fc1 -emit-llvm -O2 %s -o - | FileCheck %s --check-prefix=CHECK-AA --check-prefix=CHECK-ALL
-! RUN: %flang -fc1 -emit-llvm -O1 %s -o - | FileCheck %s --check-prefix=CHECK-AA --check-prefix=CHECK-ALL
-
-! RUN: %flang -fc1 -emit-llvm -O0 %s -o - | FileCheck %s --check-prefix=CHECK-NOAA --check-prefix=CHECK-ALL
! RUN: %flang -fc1 -emit-llvm -falias-analysis -fno-alias-analysis %s -o - | FileCheck %s --check-prefix=CHECK-NOAA --check-prefix=CHECK-ALL
! RUN: %flang -fc1 -emit-llvm %s -o - | FileCheck %s --check-prefix=CHECK-NOAA --check-prefix=CHECK-ALL
-! RUN: %flang -fc1 -emit-llvm -O3 -fno-alias-analysis %s -o - | FileCheck %s --check-prefix=CHECK-NOAA --check-prefix=CHECK-ALL
subroutine simple(a)
integer, intent(inout) :: a(:)
diff --git a/flang/test/Driver/mlir-pass-pipeline.f90 b/flang/test/Driver/mlir-pass-pipeline.f90
index 3d8c42f123e2eb0..7f92ec25bef98ec 100644
--- a/flang/test/Driver/mlir-pass-pipeline.f90
+++ b/flang/test/Driver/mlir-pass-pipeline.f90
@@ -51,8 +51,6 @@
! ALL-NEXT: 'func.func' Pipeline
! ALL-NEXT: PolymorphicOpConversion
-! O2-NEXT: AddAliasTags
-! O2-NEXT: 'func.func' Pipeline
! ALL-NEXT: CFGConversion
! ALL-NEXT: SCFToControlFlow
diff --git a/flang/test/Driver/optimization-remark.f90 b/flang/test/Driver/optimization-remark.f90
index 20ff9eb59a6702d..13fc24346eac68b 100644
--- a/flang/test/Driver/optimization-remark.f90
+++ b/flang/test/Driver/optimization-remark.f90
@@ -41,24 +41,28 @@
! Once we start filtering, this is reduced to 1 one of the loop passes.
! PASS-REGEX-LOOP-ONLY-NOT: optimization-remark.f90:77:7: remark: hoisting load [-Rpass=licm]
-! PASS-REGEX-LOOP-ONLY: optimization-remark.f90:79:5: remark: Loop deleted because it is invariant [-Rpass=loop-delete]
+! PASS-REGEX-LOOP-ONLY: optimization-remark.f90:83:5: remark: Loop deleted because it is invariant [-Rpass=loop-delete]
! MISSED-REGEX-LOOP-ONLY-NOT: optimization-remark.f90:77:7: remark: failed to hoist load with loop-invariant address because load is conditionally executed [-Rpass-missed=licm]
-! MISSED-REGEX-LOOP-ONLY: optimization-remark.f90:72:4: remark: loop not vectorized [-Rpass-missed=loop-vectorize]
+! MISSED-REGEX-LOOP-ONLY: optimization-remark.f90:76:4: remark: loop not vectorized [-Rpass-missed=loop-vectorize]
-! ANALYSIS-REGEX-LOOP-ONLY: optimization-remark.f90:73:7: remark: loop not vectorized: cannot identify array bounds [-Rpass-analysis=loop-vectorize]
+! ANALYSIS-REGEX-LOOP-ONLY: optimization-remark.f90:79:7: remark: loop not vectorized: unsafe dependent memory operations in loop. Use #pragma clang loop distribute(enable) to allow loop distribution to attempt to isolate the offending operations into a separate loop
+! ANALYSIS-REGEX-LOOP-ONLY: Unknown data dependence. Memory location is the same as accessed at optimization-remark.f90:78:7 [-Rpass-analysis=loop-vectorize]
! ANALYSIS-REGEX-LOOP-ONLY-NOT: remark: {{.*}}: IR instruction count changed from {{[0-9]+}} to {{[0-9]+}}; Delta: {{-?[0-9]+}} [-Rpass-analysis=size-info]
-! PASS: optimization-remark.f90:79:5: remark: Loop deleted because it is invariant [-Rpass=loop-delete]
+! PASS: optimization-remark.f90:77:7: remark: hoisting load [-Rpass=licm]
+! PASS: optimization-remark.f90:83:5: remark: Loop deleted because it is invariant [-Rpass=loop-delete]
-! MISSED: optimization-remark.f90:73:7: remark: failed to move load with loop-invariant address because the loop may invalidate its value [-Rpass-missed=licm]
-! MISSED: optimization-remark.f90:72:4: remark: loop not vectorized [-Rpass-missed=loop-vectorize]
-! MISSED-NOT: optimization-remark.f90:75:7: remark: loop not vectorized: unsafe dependent memory operations in loop. Use #pragma clang loop distribute(enable) to allow loop distribution to attempt to isolate the offending operations into a separate loop
+! MISSED: optimization-remark.f90:77:7: remark: failed to hoist load with loop-invariant address because load is conditionally executed [-Rpass-missed=licm]
+! MISSED: optimization-remark.f90:76:4: remark: loop not vectorized [-Rpass-missed=loop-vectorize]
+! MISSED-NOT: optimization-remark.f90:79:7: remark: loop not vectorized: unsafe dependent memory operations in loop. Use #pragma clang loop distribute(enable) to allow loop distribution to attempt to isolate the offending operations into a separate loop
! MISSED-NOT: Unknown data dependence. Memory location is the same as accessed at optimization-remark.f90:78:7 [-Rpass-analysis=loop-vectorize]
-! ANALYSIS: optimization-remark.f90:74:7: remark: loop not vectorized: unsafe dependent memory operations in loop.
-! ANALYSIS: remark: {{.*}} instructions in function [-Rpass-analysis=asm-printer]
+! ANALYSIS: optimization-remark.f90:79:7: remark: loop not vectorized: unsafe dependent memory operations in loop. Use #pragma clang loop distribute(enable) to allow loop distribution to attempt to isolate the offending operations into a separate loop
+! ANALYSIS: Unknown data dependence. Memory location is the same as accessed at optimization-remark.f90:78:7 [-Rpass-analysis=loop-vectorize]
+! ANALYSIS: remark: {{.*}}: IR instruction count changed from {{[0-9]+}} to {{[0-9]+}}; Delta: {{-?[0-9]+}} [-Rpass-analysis=size-info]
+! ANALYSIS-NOT: optimization-remark.f90:77:7: remark: failed to hoist load with loop-invariant address because load is conditionally executed [-Rpass-missed=licm]
subroutine swap_real(a1, a2)
implicit none
diff --git a/flang/test/Fir/basic-program.fir b/flang/test/Fir/basic-program.fir
index d8a9e74c318ce18..0e82f7dfdedb447 100644
--- a/flang/test/Fir/basic-program.fir
+++ b/flang/test/Fir/basic-program.fir
@@ -57,10 +57,6 @@ func.func @_QQmain() {
// PASSES-NEXT: 'func.func' Pipeline
// PASSES-NEXT: PolymorphicOpConversion
-
-// PASSES-NEXT: AddAliasTags
-
-// PASSES-NEXT: 'func.func' Pipeline
// PASSES-NEXT: CFGConversion
// PASSES-NEXT: SCFToControlFlow
diff --git a/flang/tools/tco/tco.cpp b/flang/tools/tco/tco.cpp
index a649535a39b74b3..31d6bac142dc421 100644
--- a/flang/tools/tco/tco.cpp
+++ b/flang/tools/tco/tco.cpp
@@ -120,7 +120,6 @@ compileFIR(const mlir::PassPipelineCLParser &passPipeline) {
return mlir::failure();
} else {
MLIRToLLVMPassPipelineConfig config(llvm::OptimizationLevel::O2);
- config.AliasAnalysis = true; // enabled when optimizing for speed
if (codeGenLLVM) {
// Run only CodeGen passes.
fir::createDefaultFIRCodeGenPassPipeline(pm, config);
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