[clang] 074323c - [Driver] Default to -momit-leaf-frame-pointer for AArch64

[Fangrui Song via cfe-commits]

Author: Fangrui Song
Date: 2019-12-13T18:48:34-08:00
New Revision: 074323c84658e51522e7d8d3d0179e53004b219c

URL: https://github.com/llvm/llvm-project/commit/074323c84658e51522e7d8d3d0179e53004b219c
DIFF: https://github.com/llvm/llvm-project/commit/074323c84658e51522e7d8d3d0179e53004b219c.diff

LOG: [Driver] Default to -momit-leaf-frame-pointer for AArch64

This matches https://gcc.gnu.org/onlinedocs/gcc/AArch64-Options.html

> -momit-leaf-frame-pointer
> -mno-omit-leaf-frame-pointer
>
>   Omit or keep the frame pointer in leaf functions. The former behavior is the default.

-mno-omit-leaf-frame-pointer is currently a no-op because
TargetOptions::DisableFramePointerElim is only considered for non-leaf
functions.

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D71167

Added: 
    

Modified: 
    clang/lib/Driver/ToolChains/Clang.cpp
    clang/test/Driver/cl-options.c
    clang/test/Driver/frame-pointer-elim.c

Removed: 
    


################################################################################
diff  --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index 1ba755622136..5c28a3ab1735 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -603,9 +603,9 @@ getFramePointerKind(const ArgList &Args, const llvm::Triple &Triple) {
   bool OmitFP = A && A->getOption().matches(options::OPT_fomit_frame_pointer);
   bool NoOmitFP =
       A && A->getOption().matches(options::OPT_fno_omit_frame_pointer);
-  bool KeepLeaf =
-      Args.hasFlag(options::OPT_momit_leaf_frame_pointer,
-                   options::OPT_mno_omit_leaf_frame_pointer, Triple.isPS4CPU());
+  bool KeepLeaf = Args.hasFlag(options::OPT_momit_leaf_frame_pointer,
+                               options::OPT_mno_omit_leaf_frame_pointer,
+                               Triple.isAArch64() || Triple.isPS4CPU());
   if (NoOmitFP || mustUseNonLeafFramePointerForTarget(Triple) ||
       (!OmitFP && useFramePointerForTargetByDefault(Args, Triple))) {
     if (KeepLeaf)

diff  --git a/clang/test/Driver/cl-options.c b/clang/test/Driver/cl-options.c
index b82d69b6430a..2a5453b10d26 100644
--- a/clang/test/Driver/cl-options.c
+++ b/clang/test/Driver/cl-options.c
@@ -182,7 +182,7 @@
 // Oy_2: -O2
 
 // RUN: %clang_cl --target=aarch64-pc-windows-msvc -Werror /Oy- /O2 -### -- %s 2>&1 | FileCheck -check-prefix=Oy_aarch64 %s
-// Oy_aarch64: -mframe-pointer=all
+// Oy_aarch64: -mframe-pointer=non-leaf
 // Oy_aarch64: -O2
 
 // RUN: %clang_cl --target=i686-pc-win32 -Werror /O2 /O2 -### -- %s 2>&1 | FileCheck -check-prefix=O2O2 %s

diff  --git a/clang/test/Driver/frame-pointer-elim.c b/clang/test/Driver/frame-pointer-elim.c
index 099df7175f67..47c1c0549212 100644
--- a/clang/test/Driver/frame-pointer-elim.c
+++ b/clang/test/Driver/frame-pointer-elim.c
@@ -90,7 +90,9 @@
 // WARN-OMIT-LEAF-7S-NOT: warning: optimization flag '-momit-leaf-frame-pointer' is not supported for target 'armv7s'
 // WARN-OMIT-LEAF-7S: "-mframe-pointer=non-leaf"
 
-// On the PS4, we default to omitting the frame pointer on leaf functions
+// On AArch64 and PS4, default to omitting the frame pointer on leaf functions
+// RUN: %clang -### -target aarch64 -S %s 2>&1 | \
+// RUN:   FileCheck --check-prefix=KEEP-NON-LEAF %s
 // RUN: %clang -### -target x86_64-scei-ps4 -S %s 2>&1 | \
 // RUN:   FileCheck --check-prefix=KEEP-NON-LEAF %s
 // RUN: %clang -### -target x86_64-scei-ps4 -S -O2 %s 2>&1 | \