Revert "[Flang][Driver] Add a flag to control zero initialization of global v…"

[kiranchandramohan]

Reverts #122144

Reverting due to CI failure https://lab.llvm.org/buildbot/#/builders/89/builds/14422

[llvmbot]

@llvm/pr-subscribers-clang-driver
@llvm/pr-subscribers-flang-fir-hlfir

@llvm/pr-subscribers-clang

Author: Kiran Chandramohan (kiranchandramohan)

Changes

Reverts llvm/llvm-project#122144

Reverting due to CI failure https://lab.llvm.org/buildbot/#/builders/89/builds/14422

---

Full diff: https://github.com/llvm/llvm-project/pull/123067.diff

8 Files Affected:

• (modified) clang/include/clang/Driver/Options.td (-5)
• (modified) clang/lib/Driver/ToolChains/Flang.cpp (+1-3)
• (modified) flang/include/flang/Lower/LoweringOptions.def (-3)
• (modified) flang/lib/Frontend/CompilerInvocation.cpp (-8)
• (modified) flang/lib/Lower/ConvertVariable.cpp (+1-5)
• (removed) flang/test/Driver/fno-zero-init.f90 (-9)
• (removed) flang/test/Lower/zero_init.f90 (-17)
• (removed) flang/test/Lower/zero_init_default_init.f90 (-19)

diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
index dacfca910acc40..2721c1b5d8dc55 100644
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -3505,11 +3505,6 @@ 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]>;
-defm init_global_zero : BoolOptionWithoutMarshalling<"f", "init-global-zero",
-  PosFlag<SetTrue, [], [FlangOption, FC1Option],
-          "Zero initialize globals without default initialization (default)">,
-  NegFlag<SetFalse, [], [FlangOption, FC1Option],
-          "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 c46e8222a9631a..a7d0cc99f27d2d 100644
--- a/clang/lib/Driver/ToolChains/Flang.cpp
+++ b/clang/lib/Driver/ToolChains/Flang.cpp
@@ -155,9 +155,7 @@ void Flang::addCodegenOptions(const ArgList &Args,
                    options::OPT_flang_deprecated_no_hlfir,
                    options::OPT_fno_ppc_native_vec_elem_order,
                    options::OPT_fppc_native_vec_elem_order,
-                   options::OPT_finit_global_zero,
-                   options::OPT_fno_init_global_zero, options::OPT_ftime_report,
-                   options::OPT_ftime_report_EQ});
+                   options::OPT_ftime_report, options::OPT_ftime_report_EQ});
 }
 
 void Flang::addPicOptions(const ArgList &Args, ArgStringList &CmdArgs) const {
diff --git a/flang/include/flang/Lower/LoweringOptions.def b/flang/include/flang/Lower/LoweringOptions.def
index 396c91948be36b..5a6debfdffe030 100644
--- a/flang/include/flang/Lower/LoweringOptions.def
+++ b/flang/include/flang/Lower/LoweringOptions.def
@@ -44,8 +44,5 @@ 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(InitGlobalZero, unsigned, 1, 1)
 #undef LOWERINGOPT
 #undef ENUM_LOWERINGOPT
diff --git a/flang/lib/Frontend/CompilerInvocation.cpp b/flang/lib/Frontend/CompilerInvocation.cpp
index 78d1199c19749b..5e7127313c1335 100644
--- a/flang/lib/Frontend/CompilerInvocation.cpp
+++ b/flang/lib/Frontend/CompilerInvocation.cpp
@@ -1373,14 +1373,6 @@ bool CompilerInvocation::createFromArgs(
     invoc.loweringOpts.setNoPPCNativeVecElemOrder(true);
   }
 
-  // -f[no-]init-global-zero
-  if (args.hasFlag(clang::driver::options::OPT_finit_global_zero,
-                   clang::driver::options::OPT_fno_init_global_zero,
-                   /*default=*/true))
-    invoc.loweringOpts.setInitGlobalZero(true);
-  else
-    invoc.loweringOpts.setInitGlobalZero(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 87236dc293ebbc..9ee42d5cd88002 100644
--- a/flang/lib/Lower/ConvertVariable.cpp
+++ b/flang/lib/Lower/ConvertVariable.cpp
@@ -635,11 +635,7 @@ static fir::GlobalOp defineGlobal(Fortran::lower::AbstractConverter &converter,
       global.setLinkName(builder.createCommonLinkage());
     Fortran::lower::createGlobalInitialization(
         builder, global, [&](fir::FirOpBuilder &builder) {
-          mlir::Value initValue;
-          if (converter.getLoweringOptions().getInitGlobalZero())
-            initValue = builder.create<fir::ZeroOp>(loc, symTy);
-          else
-            initValue = builder.create<fir::UndefOp>(loc, symTy);
+          mlir::Value initValue = builder.create<fir::ZeroOp>(loc, symTy);
           builder.create<fir::HasValueOp>(loc, initValue);
         });
   }
diff --git a/flang/test/Driver/fno-zero-init.f90 b/flang/test/Driver/fno-zero-init.f90
deleted file mode 100644
index 2ffa10dd040d52..00000000000000
--- a/flang/test/Driver/fno-zero-init.f90
+++ /dev/null
@@ -1,9 +0,0 @@
-! Check that the driver passes through -f[no-]init-global-zero:
-! RUN: %flang -### -S -finit-global-zero %s -o - 2>&1 | FileCheck --check-prefix=CHECK-POS %s
-! RUN: %flang -### -S -fno-init-global-zero %s -o - 2>&1 | FileCheck --check-prefix=CHECK-NEG %s
-! Check that the compiler accepts -f[no-]init-global-zero:
-! RUN: %flang_fc1 -emit-hlfir -finit-global-zero %s -o -
-! RUN: %flang_fc1 -emit-hlfir -fno-init-global-zero %s -o -
-
-! CHECK-POS: "-fc1"{{.*}}"-finit-global-zero"
-! CHECK-NEG: "-fc1"{{.*}}"-fno-init-global-zero"
diff --git a/flang/test/Lower/zero_init.f90 b/flang/test/Lower/zero_init.f90
deleted file mode 100644
index 89e6584f410f7c..00000000000000
--- a/flang/test/Lower/zero_init.f90
+++ /dev/null
@@ -1,17 +0,0 @@
-! RUN: %flang_fc1 -emit-hlfir -o - %s | FileCheck --check-prefix=CHECK-DEFAULT %s
-! RUN: %flang_fc1 -finit-global-zero -emit-hlfir -o - %s | FileCheck --check-prefix=CHECK-DEFAULT %s
-! RUN: %flang_fc1 -fno-init-global-zero -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
deleted file mode 100644
index 761052b5b08a0e..00000000000000
--- a/flang/test/Lower/zero_init_default_init.f90
+++ /dev/null
@@ -1,19 +0,0 @@
-! RUN: %flang_fc1 -emit-hlfir -o - %s | FileCheck %s
-! RUN: %flang_fc1 -finit-global-zero -emit-hlfir -o - %s | FileCheck %s
-! RUN: %flang_fc1 -fno-init-global-zero -emit-hlfir -o - %s | FileCheck %s
-
-! Test that the flag does not affect globals with default init
-
-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:  }