llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-flang-driver @llvm/pr-subscribers-clang-driver Author: Kiran Chandramohan (kiranchandramohan) <details> <summary>Changes</summary> …ariables Patch adds a flag to control zero initialization of global variables without default initialization. The default is to zero initialize. --- Full diff: https://github.com/llvm/llvm-project/pull/122144.diff 7 Files Affected: - (modified) clang/include/clang/Driver/Options.td (+3) - (modified) clang/lib/Driver/ToolChains/Flang.cpp (+1) - (modified) flang/include/flang/Lower/LoweringOptions.def (+3) - (modified) flang/lib/Frontend/CompilerInvocation.cpp (+6) - (modified) flang/lib/Lower/ConvertVariable.cpp (+5-2) - (added) flang/test/Lower/zero_init.f90 (+16) - (added) flang/test/Lower/zero_init_default_init.f90 (+16) ``````````diff diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td index 52823430919de4..e8d18cf78e985a 100644 --- a/clang/include/clang/Driver/Options.td +++ b/clang/include/clang/Driver/Options.td @@ -3494,6 +3494,9 @@ def fno_struct_path_tbaa : Flag<["-"], "fno-struct-path-tbaa">, Group<f_Group>; def fno_strict_enums : Flag<["-"], "fno-strict-enums">, Group<f_Group>; def fno_strict_overflow : Flag<["-"], "fno-strict-overflow">, Group<f_Group>, Visibility<[ClangOption, FlangOption]>; +def fno_zero_init_global_without_init : Flag<["-"], "fno-zero-init-global-without-init">, Group<f_Group>, + Visibility<[FlangOption, FC1Option]>, + HelpText<"Do not zero initialize globals without default initialization">; def fno_pointer_tbaa : Flag<["-"], "fno-pointer-tbaa">, Group<f_Group>; def fno_temp_file : Flag<["-"], "fno-temp-file">, Group<f_Group>, Visibility<[ClangOption, CC1Option, CLOption, DXCOption]>, HelpText< diff --git a/clang/lib/Driver/ToolChains/Flang.cpp b/clang/lib/Driver/ToolChains/Flang.cpp index 75b10e88371ae7..609f5315426977 100644 --- a/clang/lib/Driver/ToolChains/Flang.cpp +++ b/clang/lib/Driver/ToolChains/Flang.cpp @@ -153,6 +153,7 @@ void Flang::addCodegenOptions(const ArgList &Args, Args.addAllArgs(CmdArgs, {options::OPT_flang_experimental_hlfir, options::OPT_flang_deprecated_no_hlfir, options::OPT_fno_ppc_native_vec_elem_order, + options::OPT_fno_zero_init_global_without_init, options::OPT_fppc_native_vec_elem_order}); } diff --git a/flang/include/flang/Lower/LoweringOptions.def b/flang/include/flang/Lower/LoweringOptions.def index 5a6debfdffe030..acce21f5faab8b 100644 --- a/flang/include/flang/Lower/LoweringOptions.def +++ b/flang/include/flang/Lower/LoweringOptions.def @@ -44,5 +44,8 @@ ENUM_LOWERINGOPT(IntegerWrapAround, unsigned, 1, 0) /// If false, assume that the shapes/types/allocation-status match. ENUM_LOWERINGOPT(ReallocateLHS, unsigned, 1, 1) +/// If true, initialize globals without initialization to zero. +/// On by default. +ENUM_LOWERINGOPT(ZeroInitGlobalsWithoutInit, unsigned, 1, 1) #undef LOWERINGOPT #undef ENUM_LOWERINGOPT diff --git a/flang/lib/Frontend/CompilerInvocation.cpp b/flang/lib/Frontend/CompilerInvocation.cpp index 340efb1c63a5e5..fa91a0e2642bc8 100644 --- a/flang/lib/Frontend/CompilerInvocation.cpp +++ b/flang/lib/Frontend/CompilerInvocation.cpp @@ -1373,6 +1373,12 @@ bool CompilerInvocation::createFromArgs( invoc.loweringOpts.setNoPPCNativeVecElemOrder(true); } + // -fno-zero-init-global-without-init + if (args.hasArg( + clang::driver::options::OPT_fno_zero_init_global_without_init)) { + invoc.loweringOpts.setZeroInitGlobalsWithoutInit(false); + } + // Preserve all the remark options requested, i.e. -Rpass, -Rpass-missed or // -Rpass-analysis. This will be used later when processing and outputting the // remarks generated by LLVM in ExecuteCompilerInvocation.cpp. diff --git a/flang/lib/Lower/ConvertVariable.cpp b/flang/lib/Lower/ConvertVariable.cpp index 9ee42d5cd88002..7a422b07dd6c11 100644 --- a/flang/lib/Lower/ConvertVariable.cpp +++ b/flang/lib/Lower/ConvertVariable.cpp @@ -50,7 +50,6 @@ static llvm::cl::opt<bool> allowAssumedRank("allow-assumed-rank", llvm::cl::desc("Enable assumed rank lowering"), llvm::cl::init(true)); - #define DEBUG_TYPE "flang-lower-variable" /// Helper to lower a scalar expression using a specific symbol mapping. @@ -635,7 +634,11 @@ static fir::GlobalOp defineGlobal(Fortran::lower::AbstractConverter &converter, global.setLinkName(builder.createCommonLinkage()); Fortran::lower::createGlobalInitialization( builder, global, [&](fir::FirOpBuilder &builder) { - mlir::Value initValue = builder.create<fir::ZeroOp>(loc, symTy); + mlir::Value initValue; + if (converter.getLoweringOptions().getZeroInitGlobalsWithoutInit()) + initValue = builder.create<fir::ZeroOp>(loc, symTy); + else + initValue = builder.create<fir::UndefOp>(loc, symTy); builder.create<fir::HasValueOp>(loc, initValue); }); } diff --git a/flang/test/Lower/zero_init.f90 b/flang/test/Lower/zero_init.f90 new file mode 100644 index 00000000000000..76201eb0f0cbd0 --- /dev/null +++ b/flang/test/Lower/zero_init.f90 @@ -0,0 +1,16 @@ +! RUN: %flang_fc1 -emit-hlfir -o - %s | FileCheck --check-prefix=CHECK-DEFAULT %s +! RUN: %flang_fc1 -fno-zero-init-global-without-init -emit-hlfir -o - %s | FileCheck --check-prefix=CHECK-NO-ZERO-INIT %s + +module m1 + real :: x +end module m1 + +!CHECK-DEFAULT: fir.global @_QMm1Ex : f32 { +!CHECK-DEFAULT: %[[UNDEF:.*]] = fir.zero_bits f32 +!CHECK-DEFAULT: fir.has_value %[[UNDEF]] : f32 +!CHECK-DEFAULT: } + +!CHECK-NO-ZERO-INIT: fir.global @_QMm1Ex : f32 { +!CHECK-NO-ZERO-INIT: %[[UNDEF:.*]] = fir.undefined f32 +!CHECK-NO-ZERO-INIT: fir.has_value %[[UNDEF]] : f32 +!CHECK-NO-ZERO-INIT: } diff --git a/flang/test/Lower/zero_init_default_init.f90 b/flang/test/Lower/zero_init_default_init.f90 new file mode 100644 index 00000000000000..41ca473451b910 --- /dev/null +++ b/flang/test/Lower/zero_init_default_init.f90 @@ -0,0 +1,16 @@ +! RUN: %flang_fc1 -emit-hlfir -o - %s | FileCheck %s +! RUN: %flang_fc1 -fno-zero-init-global-without-init -emit-hlfir -o - %s | FileCheck %s + +module m2 + type val + integer :: my_val = 1 + end type val + type(val) :: v1 +end module m2 + +!CHECK: fir.global @_QMm2Ev1 : !fir.type<_QMm2Tval{my_val:i32}> { +!CHECK: %[[V1:.*]] = fir.undefined !fir.type<_QMm2Tval{my_val:i32}> +!CHECK: %[[ONE:.*]] = arith.constant 1 : i32 +!CHECK: %[[V1_INIT:.*]] = fir.insert_value %[[V1]], %[[ONE]], ["my_val", !fir.type<_QMm2Tval{my_val:i32}>] : (!fir.type<_QMm2Tval{my_val:i32}>, i32) -> !fir.type<_QMm2Tval{my_val:i32}> +!CHECK: fir.has_value %[[V1_INIT]] : !fir.type<_QMm2Tval{my_val:i32}> +!CHECK: } `````````` </details> https://github.com/llvm/llvm-project/pull/122144 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
