[clang] 5f7715d - Pass the cmdline aapcs bitfield options to cc1

[Ties Stuij via cfe-commits]

Author: Ties Stuij
Date: 2021-02-18T15:41:20Z
New Revision: 5f7715d8780a1d16ad023995d282a7d94cb923a9

URL: https://github.com/llvm/llvm-project/commit/5f7715d8780a1d16ad023995d282a7d94cb923a9
DIFF: https://github.com/llvm/llvm-project/commit/5f7715d8780a1d16ad023995d282a7d94cb923a9.diff

LOG: Pass the cmdline aapcs bitfield options to cc1

The following commits added commandline arguments to control following the Arm
Procedure Call Standard for certain volatile bitfield operations:
- https://reviews.llvm.org/D67399
- https://reviews.llvm.org/D72932

This commit fixes the oversight that these args weren't passed from the driver
to cc1 if appropriate.

Where *appropriate* means:
- `-faapcs-bitfield-width`: is the default, so won't be passed
- `-fno-aapcs-bitfield-width`: should be passed
- `-faapcs-bitfield-load`: should be passed

Differential Revision: https://reviews.llvm.org/D96784

Added: 
    clang/test/Driver/arm-aarch64-bitfield-flags.c

Modified: 
    clang/lib/Driver/ToolChains/Clang.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index eaaef6b78ffb..2fe5bbe2f06c 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -1528,6 +1528,15 @@ static void renderRemarksOptions(const ArgList &Args, ArgStringList &CmdArgs,
   }
 }
 
+void AddAAPCSVolatileBitfieldArgs(const ArgList &Args, ArgStringList &CmdArgs) {
+  if (!Args.hasFlag(options::OPT_faapcs_bitfield_width,
+                    options::OPT_fno_aapcs_bitfield_width, true))
+    CmdArgs.push_back("-fno-aapcs-bitfield-width");
+
+  if (Args.getLastArg(options::OPT_ForceAAPCSBitfieldLoad))
+    CmdArgs.push_back("-faapcs-bitfield-load");
+}
+
 namespace {
 void RenderARMABI(const llvm::Triple &Triple, const ArgList &Args,
                   ArgStringList &CmdArgs) {
@@ -1586,6 +1595,8 @@ void Clang::AddARMTargetArgs(const llvm::Triple &Triple, const ArgList &Args,
 
   if (Args.getLastArg(options::OPT_mcmse))
     CmdArgs.push_back("-mcmse");
+
+  AddAAPCSVolatileBitfieldArgs(Args, CmdArgs);
 }
 
 void Clang::RenderTargetOptions(const llvm::Triple &EffectiveTriple,
@@ -1774,6 +1785,8 @@ void Clang::AddAArch64TargetArgs(const ArgList &Args,
       D.Diag(diag::err_drv_unsupported_option_argument)
           << A->getOption().getName() << Val;
   }
+
+  AddAAPCSVolatileBitfieldArgs(Args, CmdArgs);
 }
 
 void Clang::AddMIPSTargetArgs(const ArgList &Args,

diff  --git a/clang/test/Driver/arm-aarch64-bitfield-flags.c b/clang/test/Driver/arm-aarch64-bitfield-flags.c
new file mode 100644
index 000000000000..a7961c6eedc3
--- /dev/null
+++ b/clang/test/Driver/arm-aarch64-bitfield-flags.c
@@ -0,0 +1,18 @@
+/// check -faapcs-bitfield-width/-fno-aapcs-bitfield-width
+// RUN: %clang -target arm-arm-none-eabi -march=armv8-m.main -faapcs-bitfield-width -### %s 2>&1 | FileCheck --check-prefixes=WIDTH,INVERSE-WIDTH %s
+// RUN: %clang -target aarch64-arm-none-eabi -march=armv8-m.main -faapcs-bitfield-width -### %s 2>&1 | FileCheck --check-prefixes=WIDTH,INVERSE-WIDTH %s
+// RUN: %clang -target arm-arm-none-eabi -march=armv8-m.main -fno-aapcs-bitfield-width -### %s 2>&1 | FileCheck --check-prefixes=NO-WIDTH,WIDTH %s
+// RUN: %clang -target aarch64-arm-none-eabi -march=armv8-m.main -fno-aapcs-bitfield-width -### %s 2>&1 | FileCheck --check-prefixes=NO-WIDTH,WIDTH %s
+// WIDTH-NOT: -faapcs-bitfield-width
+// NO-WIDTH: -fno-aapcs-bitfield-width
+
+/// check -faapcs-bitfield-load
+// RUN: %clang -target arm-arm-none-eabi -march=armv8-m.main -faapcs-bitfield-load -### %s 2>&1 | FileCheck --check-prefix=LOAD %s
+// RUN: %clang -target aarch64-arm-none-eabi -march=armv8-m.main -faapcs-bitfield-load -### %s 2>&1 | FileCheck --check-prefix=LOAD %s
+// LOAD: -faapcs-bitfield-load
+
+/// check absence of the above argument when not given
+// RUN: %clang -target arm-arm-none-eabi -march=armv8-m.main -### %s 2>&1 | FileCheck --check-prefixes=INVERSE-WIDTH,INVERSE-LOAD %s
+// RUN: %clang -target aarch64-arm-none-eabi -march=armv8-m.main -### %s 2>&1 | FileCheck --check-prefixes=INVERSE-WIDTH,INVERSE-LOAD %s
+// INVERSE-WIDTH-NOT: -fno-aapcs-bitfield-width
+// INVERSE-LOAD-NOT: -fno-aapcs-bitfield-load