From 359b105745cc7edf0d3c84a697de596ee331374d Mon Sep 17 00:00:00 2001 From: Sanjay Patel Date: Thu, 9 Apr 2015 15:03:23 +0000 Subject: Process the -freciprocal-math optimization flag (PR20912) The driver currently accepts but ignores the -freciprocal-math flag. This patch passes the flag through and enables 'arcp' fast-math-flag generation in IR. Note that this change does not actually enable the optimization for any target. The reassociation optimization that this flag specifies was implemented by http://reviews.llvm.org/D6334 : http://llvm.org/viewvc/llvm-project?view=revision&revision=222510 Because the optimization is done in the backend rather than IR, the backend must be modified to understand instruction-level fast-math-flags or a new function-level attribute must be created. Also note that -freciprocal-math is independent of any target-specific usage of reciprocal estimate hardware instructions. That requires its own flag ('-mrecip'). https://llvm.org/bugs/show_bug.cgi?id=20912 llvm-svn: 234493 --- clang/lib/Frontend/CompilerInvocation.cpp | 1 + 1 file changed, 1 insertion(+) (limited to 'clang/lib/Frontend/CompilerInvocation.cpp') diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp index 5d2cdae..cd0a7c4 100644 --- a/clang/lib/Frontend/CompilerInvocation.cpp +++ b/clang/lib/Frontend/CompilerInvocation.cpp @@ -451,6 +451,7 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK, Args.hasArg(OPT_cl_finite_math_only) || Args.hasArg(OPT_cl_fast_relaxed_math)); Opts.NoSignedZeros = Args.hasArg(OPT_fno_signed_zeros); + Opts.ReciprocalMath = Args.hasArg(OPT_freciprocal_math); Opts.NoZeroInitializedInBSS = Args.hasArg(OPT_mno_zero_initialized_in_bss); Opts.BackendOptions = Args.getAllArgValues(OPT_backend_option); Opts.NumRegisterParameters = getLastArgIntValue(Args, OPT_mregparm, 0, Diags); -- cgit v1.1