From 830a90189c622600305e488f4bc90baa3bdcdd26 Mon Sep 17 00:00:00 2001 From: Simon Tatham Date: Mon, 3 Jun 2019 11:02:53 +0000 Subject: [PATCH] [ARM] Fix recent breakage of -mfpu=none. The recent change D60691 introduced a bug in clang when handling option combinations such as `-mcpu=cortex-m4 -mfpu=none`. Those options together should select Cortex-M4 but disable all use of hardware FP, but in fact, now hardware FP instructions can still be generated in that mode. The reason is because the handling of FPUVersion::NONE disables all the same feature names it used to, of which the base one is `vfp2`. But now there are further features below that, like `vfp2d16fp` and (following D60694) `fpregs`, which also need to be turned off to disable hardware FP completely. Added a tiny test which double-checks that compiling a simple FP function doesn't access the FP registers. Reviewers: SjoerdMeijer, dmgreen Reviewed By: dmgreen Subscribers: lebedev.ri, javed.absar, kristof.beyls, hiraditya, cfe-commits, llvm-commits Tags: #clang, #llvm Differential Revision: https://reviews.llvm.org/D62729 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@362380 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Support/ARMTargetParser.cpp | 1 + 1 file changed, 1 insertion(+) diff --git a/lib/Support/ARMTargetParser.cpp b/lib/Support/ARMTargetParser.cpp index a33f602e532..8806ea52fdf 100644 --- a/lib/Support/ARMTargetParser.cpp +++ b/lib/Support/ARMTargetParser.cpp @@ -198,6 +198,7 @@ bool ARM::getFPUFeatures(unsigned FPUKind, std::vector &Features) { Features.push_back("-fp-armv8"); break; case FPUVersion::NONE: + Features.push_back("-fpregs"); Features.push_back("-vfp2"); Features.push_back("-vfp3"); Features.push_back("-fp16"); -- 2.40.0