[flang] add -f[no-]reciprocal-math

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

Differential Revision: https://reviews.llvm.org/D137330

6 files changed, 15 insertions, 0 deletions

diff --git a/flang/include/flang/Frontend/LangOptions.def b/flang/include/flang/Frontend/LangOptions.def
index 059e3d18dfc8..024db6109d6a 100644
--- a/flang/include/flang/Frontend/LangOptions.def
+++ b/flang/include/flang/Frontend/LangOptions.def
@@ -31,6 +31,8 @@ LANGOPT(ApproxFunc, 1, false)
 LANGOPT(NoSignedZeros, 1, false)
 /// Allow reassociation transformations for floating-point instructions
 LANGOPT(AssociativeMath, 1, false)
+/// Allow division operations to be reassociated
+LANGOPT(ReciprocalMath, 1, false)
 
 #undef LANGOPT
 #undef ENUM_LANGOPT
diff --git a/flang/lib/Frontend/CompilerInvocation.cpp b/flang/lib/Frontend/CompilerInvocation.cpp
index 8c0bdcd185b6..bb87ea285a26 100644
--- a/flang/lib/Frontend/CompilerInvocation.cpp
+++ b/flang/lib/Frontend/CompilerInvocation.cpp
@@ -726,6 +726,12 @@ static bool parseFloatingPointArgs(CompilerInvocation &invoc,
     opts.AssociativeMath = true;
   }
 
+  if (const llvm::opt::Arg *a =
+          args.getLastArg(clang::driver::options::OPT_freciprocal_math)) {
+    diags.Report(diagUnimplemented) << a->getOption().getName();
+    opts.ReciprocalMath = true;
+  }
+
   return true;
 }
 
diff --git a/flang/test/Driver/driver-help-hidden.f90 b/flang/test/Driver/driver-help-hidden.f90
index b3913e99d138..3bce2a57caa1 100644
--- a/flang/test/Driver/driver-help-hidden.f90
+++ b/flang/test/Driver/driver-help-hidden.f90
@@ -48,6 +48,7 @@
 ! CHECK-NEXT: -fno-signed-zeros      Allow optimizations that ignore the sign of floating point zeros
 ! CHECK-NEXT: -fopenacc              Enable OpenACC
 ! CHECK-NEXT: -fopenmp               Parse OpenMP pragmas and generate parallel code.
+! CHECK-NEXT: -freciprocal-math      Allow division operations to be reassociated
 ! CHECK-NEXT: -fsyntax-only          Run the preprocessor, parser and semantic analysis stages
 ! CHECK-NEXT: -fxor-operator         Enable .XOR. as a synonym of .NEQV.
 ! CHECK-NEXT: -help     Display available options
diff --git a/flang/test/Driver/driver-help.f90 b/flang/test/Driver/driver-help.f90
index 32b6f7615dec..8d24deee0b1a 100644
--- a/flang/test/Driver/driver-help.f90
+++ b/flang/test/Driver/driver-help.f90
@@ -46,6 +46,7 @@
 ! HELP-NEXT: -fno-signed-zeros      Allow optimizations that ignore the sign of floating point zeros
 ! HELP-NEXT: -fopenacc              Enable OpenACC
 ! HELP-NEXT: -fopenmp               Parse OpenMP pragmas and generate parallel code.
+! HELP-NEXT: -freciprocal-math      Allow division operations to be reassociated
 ! HELP-NEXT: -fsyntax-only          Run the preprocessor, parser and semantic analysis stages
 ! HELP-NEXT: -fxor-operator         Enable .XOR. as a synonym of .NEQV.
 ! HELP-NEXT: -help                  Display available options
@@ -128,6 +129,7 @@
 ! HELP-FC1-NEXT: -fno-signed-zeros      Allow optimizations that ignore the sign of floating point zeros
 ! HELP-FC1-NEXT: -fopenacc              Enable OpenACC
 ! HELP-FC1-NEXT: -fopenmp               Parse OpenMP pragmas and generate parallel code.
+! HELP-FC1-NEXT: -freciprocal-math      Allow division operations to be reassociated
 ! HELP-FC1-NEXT: -fsyntax-only          Run the preprocessor, parser and semantic analysis stages
 ! HELP-FC1-NEXT: -fxor-operator         Enable .XOR. as a synonym of .NEQV.
 ! HELP-FC1-NEXT: -help                  Display available options
diff --git a/flang/test/Driver/flang_fp_opts.f90 b/flang/test/Driver/flang_fp_opts.f90
index bbe886bcec87..0dc31f6f7649 100644
--- a/flang/test/Driver/flang_fp_opts.f90
+++ b/flang/test/Driver/flang_fp_opts.f90
@@ -7,6 +7,7 @@
 ! RUN:      -fapprox-func \
 ! RUN:      -fno-signed-zeros \
 ! RUN:      -mreassociate \
+! RUN:      -freciprocal-math \
 ! RUN:      %s 2>&1 | FileCheck %s
 ! CHECK: ffp-contract= is not currently implemented
 ! CHECK: menable-no-infs is not currently implemented
@@ -14,3 +15,4 @@
 ! CHECK: fapprox-func is not currently implemented
 ! CHECK: fno-signed-zeros is not currently implemented
 ! CHECK: mreassociate is not currently implemented
+! CHECK: freciprocal-math is not currently implemented
diff --git a/flang/test/Driver/frontend-forwarding.f90 b/flang/test/Driver/frontend-forwarding.f90
index de3ed6ddbfca..9d1d7cb8d3c8 100644
--- a/flang/test/Driver/frontend-forwarding.f90
+++ b/flang/test/Driver/frontend-forwarding.f90
@@ -14,6 +14,7 @@
 ! RUN:     -fapprox-func \
 ! RUN:     -fno-signed-zeros \
 ! RUN:     -fassociative-math \
+! RUN:     -freciprocal-math \
 ! RUN:     -mllvm -print-before-all\
 ! RUN:     -P \
 ! RUN:   | FileCheck %s
@@ -30,5 +31,6 @@
 ! CHECK: "-fapprox-func"
 ! CHECK: "-fno-signed-zeros"
 ! CHECK: "-mreassociate"
+! CHECK: "-freciprocal-math"
 ! CHECK: "-fconvert=little-endian"
 ! CHECK:  "-mllvm" "-print-before-all"