[flang][f18] Make -fdebug-dump-{symbols|parse-tree} imply -fsyntax-only

[awarzynski]

Summary

The following _action_ options are always used with -fsyntax-only
(also an _action_ option):

• -fdebug-dump-symbols
• -fdebug-dump-parse-tree

This patch makes the above options imply -fsyntax-only.

From the perspective of f18 this change saves typing and is otherwise
a non-functional change. But it will simplify things in the new driver,
flang-new, in which only the last action option is taken into account
and executed. In other words, the following would only run
-fsyntax-only:

flang-new -fdebug-dump-symbols -fsyntax-only <input>

whereas this would only run -fdebug-dump-symbols:

flang-new -fsyntax-only -fdebug-dump-symbols <input>

[FarisRehman]

This patch makes sense to me as the behaviour of the new driver is similar to clang in that only the last action-related option is run, e.g:

• Only -emit-llvm is run in: clang -cc1 -ast-dump -emit-llvm file.c
• Only -ast-dump is run in: clang -cc1 -emit-llvm -ast-dump file.c

This change will mean -fsyntax-only does not need to be specified when running -fdebug-dump-parse-tree or -fdebug-dump-symbols as it will always be run when either one of these action-related options are present.
LGTM!

[klausler]

These are orthogonal concepts, and I occasionally will dump symbols with f18 without using -fsyntax-only.

[awarzynski]

Apologies for disrupting your workflow. Just to double check - you want to use -fdebug-dump-symbols and then have f18 call the external compiler?

I will upload a patch that restores the original behavior in f18.

[klausler]

In D96528#2566468, @awarzynski wrote:

Apologies for disrupting your workflow. Just to double check - you want to use -fdebug-dump-symbols and then have f18 call the external compiler?

I will upload a patch that restores the original behavior in f18.

I don't think that you can do that without also reverting changes to tests, and we probably don't want to do that.

[awarzynski]

In D96528#2566476, @klausler wrote:

In D96528#2566468, @awarzynski wrote:

Apologies for disrupting your workflow. Just to double check - you want to use -fdebug-dump-symbols and then have f18 call the external compiler?

I will upload a patch that restores the original behavior in f18.

I don't think that you can do that without also reverting changes to tests, and we probably don't want to do that.

That's true, but we can update the tests to use: -fsyntax-only -fdebug-dump-parse-tree:

• this restores the original behavior for f18
• the new driver will _ignore_ -fsyntax-only and run -fdebug-dump-parse-tree only (so this would be fine for flang-new as well)

Originally some tests had -fdebug-dump-parse-tree -fsyntax-only and that order is problematic for the new driver (it only respects the last _action_).

[klausler]

In D96528#2566865, @awarzynski wrote:

In D96528#2566476, @klausler wrote:

In D96528#2566468, @awarzynski wrote:

Apologies for disrupting your workflow. Just to double check - you want to use -fdebug-dump-symbols and then have f18 call the external compiler?

I will upload a patch that restores the original behavior in f18.

I don't think that you can do that without also reverting changes to tests, and we probably don't want to do that.

That's true, but we can update the tests to use: -fsyntax-only -fdebug-dump-parse-tree:

• this restores the original behavior for f18
• the new driver will _ignore_ -fsyntax-only and run -fdebug-dump-parse-tree only (so this would be fine for flang-new as well)

Originally some tests had -fdebug-dump-parse-tree -fsyntax-only and that order is problematic for the new driver (it only respects the last _action_).

What if a compiler developer wants multiple dumps?

[awarzynski]

In D96528#2566877, @klausler wrote:

What if a compiler developer wants multiple dumps?

This is tricky. flang-new -cc1 models clang -cc1 in this respect and runs one action at a time. Diverging from this design would be challenging because then the driver would have to:

• schedule the actions (and keep track of them)
• parse options for every action separately
• resolve potential conflicts with options (e.g. one option is fine with one of the requested actions, but causes a driver/compilation error for the other)

Alternatively, we could make -fdebug-dump-parse-tree and -fdebug-dump-symbols non-action flags in flang-new. This wouldn't fit nicely into the model implemented in libclangDriver where compiler flags/options are split into:

• action flags
• set-up/config/feature flags.

I've reverted this change in https://reviews.llvm.org/D96870. Moving forward, I would like to keep the current approach in flang-new -fc1. This may mean some inconsistencies with f18 in terms of user-experience, but the alternative would be costly to implement.

flang/test/Evaluate/test_folding.sh

 src=$1
 [[ ! -f $src ]] && echo "File not found: $src" && exit 1
 shift
 
 temp=$1
 mkdir -p $temp
 shift
 
-CMD="$* -fdebug-dump-symbols -fsyntax-only"
+CMD="$* -fdebug-dump-symbols"
 
 # Check if tests should assume folding is using libpgmath
 if [[ $LIBPGMATH ]]; then
   CMD="$CMD -DTEST_LIBPGMATH"
   echo "Assuming libpgmath support"
 else
   echo "Not assuming libpgmath support"
 fi

flang/test/Semantics/data05.f90

-!RUN: %f18 -fdebug-dump-symbols -fsyntax-only %s | FileCheck %s
+!RUN: %f18 -fdebug-dump-symbols %s | FileCheck %s
 module m
   interface
     integer function ifunc(n)
       integer, intent(in) :: n
     end function
     real function rfunc(x)
       real, intent(in) :: x
     end function

flang/test/Semantics/data08.f90

-! RUN: %f18 -fdebug-dump-symbols -fsyntax-only %s 2>&1 | FileCheck %s
+! RUN: %f18 -fdebug-dump-symbols %s 2>&1 | FileCheck %s
 ! CHECK: DATA statement value initializes 'jx' of type 'INTEGER(4)' with CHARACTER
 ! CHECK: DATA statement value initializes 'jy' of type 'INTEGER(4)' with CHARACTER
 ! CHECK: DATA statement value initializes 'jz' of type 'INTEGER(4)' with CHARACTER
 ! CHECK: DATA statement value initializes 'kx' of type 'INTEGER(8)' with CHARACTER
 ! CHECK: jx (InDataStmt) size=4 offset=0: ObjectEntity type: INTEGER(4) init:1684234849_4
 ! CHECK: jy (InDataStmt) size=4 offset=4: ObjectEntity type: INTEGER(4) init:543384161_4
 ! CHECK: jz (InDataStmt) size=4 offset=8: ObjectEntity type: INTEGER(4) init:1684234849_4
 ! CHECK: kx (InDataStmt) size=8 offset=16: ObjectEntity type: INTEGER(8) init:7523094288207667809_8
 
 integer :: jx, jy, jz
 integer(8) :: kx
 data jx/4habcd/
 data jy/3habc/
 data jz/5habcde/
 data kx/'abcdefgh'/
 end

flang/test/Semantics/offsets01.f90

-!RUN: %f18 -fdebug-dump-symbols -fsyntax-only %s | FileCheck %s
+!RUN: %f18 -fdebug-dump-symbols %s | FileCheck %s
 
 ! Size and alignment of intrinsic types
 subroutine s1
   integer(1) :: a_i1  !CHECK: a_i1 size=1 offset=0:
   integer(8) :: b_i8  !CHECK: b_i8 size=8 offset=8:
   real(2)    :: c_r2  !CHECK: c_r2 size=2 offset=16:
   real(2)    :: d_r2  !CHECK: d_r2 size=2 offset=18:
   real(8)    :: e_r8  !CHECK: e_r8 size=8 offset=24:

flang/test/Semantics/offsets02.f90

-!RUN: %f18 -fdebug-dump-symbols -fsyntax-only %s | FileCheck %s
+!RUN: %f18 -fdebug-dump-symbols %s | FileCheck %s
 
 ! Size and alignment of derived types
 
 ! Array of derived type with 64-bit alignment
 subroutine s1
   type t1
     real(8) :: a
     real(4) :: b

flang/test/Semantics/offsets03.f90

-!RUN: %f18 -fdebug-dump-symbols -fsyntax-only %s | FileCheck %s
+!RUN: %f18 -fdebug-dump-symbols %s | FileCheck %s
 
 ! Size and alignment with EQUIVALENCE and COMMON
 
 ! a1 depends on a2 depends on a3
 module ma
   real :: a1(10), a2(10), a3(10)
   equivalence(a1, a2(3)) !CHECK: a1, PUBLIC size=40 offset=20:
   equivalence(a2, a3(4)) !CHECK: a2, PUBLIC size=40 offset=12:

flang/test/Semantics/oldparam01.f90

-! RUN: %f18 -falternative-parameter-statement -fdebug-dump-symbols -fsyntax-only %s 2>&1 | FileCheck %s
+! RUN: %f18 -falternative-parameter-statement -fdebug-dump-symbols %s 2>&1 | FileCheck %s
 
 ! Non-error tests for "old style" PARAMETER statements
 
 type :: t
   integer(kind=4) :: n
 end type
 !CHECK: x1, PARAMETER size=4 offset=0: ObjectEntity type: INTEGER(4) init:1_4
 parameter x1 = 1_4 ! integer scalar

flang/test/Semantics/oldparam02.f90

-! RUN: not %f18 -falternative-parameter-statement -fdebug-dump-symbols -fsyntax-only %s 2>&1 | FileCheck %s
+! RUN: not %f18 -falternative-parameter-statement -fdebug-dump-symbols %s 2>&1 | FileCheck %s
 
 ! Error tests for "old style" PARAMETER statements
 subroutine subr(x1,x2,x3,x4,x5)
   type(*), intent(in) :: x1
   class(*), intent(in) :: x2
   real, intent(in) :: x3(*)
   real, intent(in) :: x4(:)
   character(*), intent(in) :: x5

flang/test/Semantics/resolve100.f90

-!RUN: %f18 -fdebug-dump-symbols -fsyntax-only %s | FileCheck %s
+!RUN: %f18 -fdebug-dump-symbols %s | FileCheck %s
 
 program p
   ! CHECK: a size=4 offset=0: ObjectEntity type: LOGICAL(4)
   ! CHECK: b size=4 offset=4: ObjectEntity type: REAL(4)
   logical :: a = .false.
   real :: b = 9.73
   ! CHECK: a: AssocEntity type: REAL(4) expr:b
   ! CHECK: b: AssocEntity type: LOGICAL(4) expr:a
   associate (b => a, a => b)
     print*, a, b
   end associate
   print*, a, b
 end

flang/test/Semantics/rewrite01.f90

-! RUN: %f18 -fsyntax-only -fdebug-dump-parse-tree %s 2>&1 | FileCheck %s
+! RUN: %f18 -fdebug-dump-parse-tree %s 2>&1 | FileCheck %s
 ! Ensure that READ(CVAR) [, item-list] is corrected when CVAR is a
 ! character variable so as to be a formatted read from the default
 ! unit, not an unformatted read from an internal unit (which is not
 ! possible in Fortran).
 character :: cvar
 ! CHECK-NOT: IoUnit -> Variable -> Designator -> DataRef -> Name = 'cvar'
 ! CHECK: Format -> Expr = 'cvar'
 read(cvar)
 end

flang/test/Semantics/typeinfo01.f90

-!RUN: %f18 -fdebug-dump-symbols -fsyntax-only %s | FileCheck %s
+!RUN: %f18 -fdebug-dump-symbols %s | FileCheck %s
 ! Tests for derived type runtime descriptions
 
 module m01
   type :: t1
     integer :: n
   end type
 !CHECK: .c.t1, SAVE, TARGET: ObjectEntity type: TYPE(component) shape: 0_8:0_8 init:[component::component(name=.n.n,genre=1_1,category=0_1,kind=4_1,rank=0_1,offset=0_8,characterlen=value(genre=1_1,value=0_8),derived=NULL(),lenvalue=NULL(),bounds=NULL(),initialization=NULL())]
 !CHECK: .dt.t1, SAVE, TARGET: ObjectEntity type: TYPE(derivedtype) init:derivedtype(binding=NULL(),name=.n.t1,sizeinbytes=4_8,parent=NULL(),uninstantiated=NULL(),kindparameter=NULL(),lenparameterkind=NULL(),component=.c.t1,procptr=NULL(),special=NULL())

flang/tools/f18/f18.cpp

while (!args.empty()) {
     } else if (arg == "-falternative-parameter-statement") {
       options.features.Enable(
           Fortran::common::LanguageFeature::OldStyleParameter, true);
     } else if (arg == "-fdebug-dump-provenance") {
       driver.dumpProvenance = true;
       options.needProvenanceRangeToCharBlockMappings = true;
     } else if (arg == "-fdebug-dump-parse-tree") {
       driver.dumpParseTree = true;
+      driver.syntaxOnly = true;
     } else if (arg == "-fdebug-pre-fir-tree") {
       driver.dumpPreFirTree = true;
     } else if (arg == "-fdebug-dump-symbols") {
       driver.dumpSymbols = true;
+      driver.syntaxOnly = true;
     } else if (arg == "-fdebug-module-writer") {
       driver.debugModuleWriter = true;
     } else if (arg == "-fdebug-measure-parse-tree") {
       driver.measureTree = true;
     } else if (arg == "-fdebug-instrumented-parse") {
       options.instrumentedParse = true;
     } else if (arg == "-fdebug-no-semantics") {
       driver.debugNoSemantics = true;