[flang] Add -f[no-]honor-nans and -menable-no-nans

Only add the option processing and store the result. No attributes are
added to FIR yet.

Differential Revision: https://reviews.llvm.org/D137325

5 files changed, 17 insertions, 1 deletions

diff --git a/flang/include/flang/Frontend/LangOptions.def b/flang/include/flang/Frontend/LangOptions.def
index 96e9ea63f196..6bafc0613d3b 100644
--- a/flang/include/flang/Frontend/LangOptions.def
+++ b/flang/include/flang/Frontend/LangOptions.def
@@ -23,6 +23,8 @@ ENUM_LANGOPT(FPContractMode, FPModeKind, 2, FPM_Off) ///< FP Contract Mode (off/
 
 /// Permit floating point optimization without regard to infinities
 LANGOPT(NoHonorInfs, 1, false)
+/// Permit floating point optimization without regard to NaN
+LANGOPT(NoHonorNaNs, 1, false)
 
 #undef LANGOPT
 #undef ENUM_LANGOPT
diff --git a/flang/lib/Frontend/CompilerInvocation.cpp b/flang/lib/Frontend/CompilerInvocation.cpp
index 252e1a7e697a..cce97caea515 100644
--- a/flang/lib/Frontend/CompilerInvocation.cpp
+++ b/flang/lib/Frontend/CompilerInvocation.cpp
@@ -702,6 +702,12 @@ static bool parseFloatingPointArgs(CompilerInvocation &invoc,
     opts.NoHonorInfs = true;
   }
 
+  if (const llvm::opt::Arg *a =
+          args.getLastArg(clang::driver::options::OPT_menable_no_nans)) {
+    diags.Report(diagUnimplemented) << a->getOption().getName();
+    opts.NoHonorNaNs = true;
+  }
+
   return true;
 }
 
diff --git a/flang/test/Driver/driver-help.f90 b/flang/test/Driver/driver-help.f90
index 068985bc6d56..587c0ec2ffcb 100644
--- a/flang/test/Driver/driver-help.f90
+++ b/flang/test/Driver/driver-help.f90
@@ -131,6 +131,7 @@
 ! HELP-FC1-NEXT: -I <dir>               Add directory to the end of the list of include search paths
 ! HELP-FC1-NEXT: -load <dsopath>        Load the named plugin (dynamic shared object)
 ! HELP-FC1-NEXT: -menable-no-infs       Allow optimization to assume there are no infinities.
+! HELP-FC1-NEXT: -menable-no-nans       Allow optimization to assume there are no NaNs.
 ! HELP-FC1-NEXT: -mllvm <value>         Additional arguments to forward to LLVM's option processing
 ! HELP-FC1-NEXT: -mmlir <value>         Additional arguments to forward to MLIR's option processing
 ! HELP-FC1-NEXT: -module-dir <dir>      Put MODULE files in <dir>
diff --git a/flang/test/Driver/flang_fp_opts.f90 b/flang/test/Driver/flang_fp_opts.f90
index 272ef8495b95..79f1ba796a4a 100644
--- a/flang/test/Driver/flang_fp_opts.f90
+++ b/flang/test/Driver/flang_fp_opts.f90
@@ -1,5 +1,10 @@
 ! Test for handling of floating point options within the frontend driver
 
-! RUN: %flang_fc1 -ffp-contract=fast -menable-no-infs %s 2>&1 | FileCheck %s
+! RUN: %flang_fc1 \
+! RUN:      -ffp-contract=fast \
+! RUN:      -menable-no-infs \
+! RUN:      -menable-no-nans \
+! RUN:      %s 2>&1 | FileCheck %s
 ! CHECK: ffp-contract= is not currently implemented
 ! CHECK: menable-no-infs is not currently implemented
+! CHECK: menable-no-nans is not currently implemented
diff --git a/flang/test/Driver/frontend-forwarding.f90 b/flang/test/Driver/frontend-forwarding.f90
index 0c3fd6c48ee2..1160509a500c 100644
--- a/flang/test/Driver/frontend-forwarding.f90
+++ b/flang/test/Driver/frontend-forwarding.f90
@@ -10,6 +10,7 @@
 ! RUN:     -fconvert=little-endian \
 ! RUN:     -ffp-contract=fast \
 ! RUN:     -fno-honor-infinities \
+! RUN:     -fno-honor-nans \
 ! RUN:     -mllvm -print-before-all\
 ! RUN:     -P \
 ! RUN:   | FileCheck %s
@@ -22,5 +23,6 @@
 ! CHECK: "-flarge-sizes"
 ! CHECK: "-ffp-contract=fast"
 ! CHECK: "-menable-no-infs"
+! CHECK: "-menable-no-nans"
 ! CHECK: "-fconvert=little-endian"
 ! CHECK:  "-mllvm" "-print-before-all"