[clang] 0a23fbd - clang: Always pass PowerPC endian information to GNU as
Nick Desaulniers via cfe-commits
cfe-commits at lists.llvm.org
Mon Jan 11 14:50:57 PST 2021
Author: Nathan Chancellor
Date: 2021-01-11T14:50:28-08:00
New Revision: 0a23fbd28c7509f2f980946091e6055bf27164d2
URL: https://github.com/llvm/llvm-project/commit/0a23fbd28c7509f2f980946091e6055bf27164d2
DIFF: https://github.com/llvm/llvm-project/commit/0a23fbd28c7509f2f980946091e6055bf27164d2.diff
LOG: clang: Always pass PowerPC endian information to GNU as
When building a 64-bit big endian PowerPC Linux kernel with a 64-bit
little endian PowerPC target, the 32-bit vDSO errors:
```
$ make ARCH=powerpc CC=clang CROSS_COMPILE=powerpc64le-linux-gnu- \
pseries_defconfig arch/powerpc/kernel/vdso32/
ld.lld: error: arch/powerpc/kernel/vdso32/sigtramp.o is incompatible with elf32-powerpc
ld.lld: error: arch/powerpc/kernel/vdso32/gettimeofday.o is incompatible with elf32-powerpc
ld.lld: error: arch/powerpc/kernel/vdso32/datapage.o is incompatible with elf32-powerpc
ld.lld: error: arch/powerpc/kernel/vdso32/cacheflush.o is incompatible with elf32-powerpc
ld.lld: error: arch/powerpc/kernel/vdso32/note.o is incompatible with elf32-powerpc
ld.lld: error: arch/powerpc/kernel/vdso32/getcpu.o is incompatible with elf32-powerpc
ld.lld: error: arch/powerpc/kernel/vdso32/vgettimeofday.o is incompatible with elf32-powerpc
...
```
This happens because the endian information is missing from the call to
the assembler, even though it was explicitly passed to clang. See the
below example.
```
$ echo | clang --target=powerpc64le-linux-gnu \
--prefix=/usr/bin/powerpc64le-linux-gnu- \
-no-integrated-as -m32 -mbig-endian -### -x c -c -
".../clang-12" "-cc1" "-triple" "powerpc-unknown-linux-gnu" ...
...
"/usr/bin/powerpc64le-linux-gnu-as" "-a32" "-mppc" "-many" "-o" "-.o" "/tmp/--e69e28.s"
```
clang sets the right target with -m32 and -mbig-endian but -mbig-endian
does not make it to the assembler, resulting in a 32-bit little endian
binary. This differs from the little endian targets, which always pass
-mlittle-endian.
```
$ echo | clang --target=powerpc64-linux-gnu \
--prefix=/usr/bin/powerpc64-linux-gnu- \
-no-integrated-as -m32 -mlittle-endian -### -x c -c -
".../clang-12" "-cc1" "-triple" "powerpcle-unknown-linux-gnu" ...
...
"/usr/bin/powerpc64-linux-gnu-as" "-a32" "-mppc" "-mlittle-endian" "-many" "-o" "-.o" "/tmp/--405dbd.s"
```
Do the same thing for the big endian targets so that there is no more
error. This matches GCC's behavior, where -mbig and -mlittle are always
passed along to GNU as.
```
$ echo | powerpc64-linux-gcc -### -x c -c -
...
.../powerpc64-linux/bin/as -a64 -mpower4 -many -mbig -o -.o /tmp/ccVn7NAm.s
...
$ echo | powerpc64le-linux-gcc -### -x c -c -
...
.../powerpc64le-linux/bin/as -a64 -mpower8 -many -mlittle -o -.o /tmp/ccPN9ato.s
...
```
Reviewed By: nickdesaulniers, MaskRay
Differential Revision: https://reviews.llvm.org/D94442
Added:
Modified:
clang/lib/Driver/ToolChains/Gnu.cpp
clang/test/Driver/ppc-features.cpp
Removed:
################################################################################
diff --git a/clang/lib/Driver/ToolChains/Gnu.cpp b/clang/lib/Driver/ToolChains/Gnu.cpp
index 1633334cf6e7..1d8a3cdce92a 100644
--- a/clang/lib/Driver/ToolChains/Gnu.cpp
+++ b/clang/lib/Driver/ToolChains/Gnu.cpp
@@ -731,6 +731,7 @@ void tools::gnutools::Assembler::ConstructJob(Compilation &C,
case llvm::Triple::ppc: {
CmdArgs.push_back("-a32");
CmdArgs.push_back("-mppc");
+ CmdArgs.push_back("-mbig-endian");
CmdArgs.push_back(
ppc::getPPCAsmModeForCPU(getCPUName(Args, getToolChain().getTriple())));
break;
@@ -746,6 +747,7 @@ void tools::gnutools::Assembler::ConstructJob(Compilation &C,
case llvm::Triple::ppc64: {
CmdArgs.push_back("-a64");
CmdArgs.push_back("-mppc64");
+ CmdArgs.push_back("-mbig-endian");
CmdArgs.push_back(
ppc::getPPCAsmModeForCPU(getCPUName(Args, getToolChain().getTriple())));
break;
diff --git a/clang/test/Driver/ppc-features.cpp b/clang/test/Driver/ppc-features.cpp
index 05d71b95dba7..85060951aa16 100644
--- a/clang/test/Driver/ppc-features.cpp
+++ b/clang/test/Driver/ppc-features.cpp
@@ -156,14 +156,25 @@
// CHECK-NOSPE: "-target-feature" "-spe"
// Assembler features
-// RUN: %clang -target powerpc64-unknown-linux-gnu %s -### -o %t.o -no-integrated-as 2>&1 | FileCheck -check-prefix=CHECK_BE_AS_ARGS %s
-// CHECK_BE_AS_ARGS: "-mppc64"
-// CHECK_BE_AS_ARGS: "-many"
-
-// RUN: %clang -target powerpc64le-unknown-linux-gnu %s -### -o %t.o -no-integrated-as 2>&1 | FileCheck -check-prefix=CHECK_LE_AS_ARGS %s
-// CHECK_LE_AS_ARGS: "-mppc64"
-// CHECK_LE_AS_ARGS: "-mlittle-endian"
-// CHECK_LE_AS_ARGS: "-mpower8"
+// RUN: %clang -target powerpc-unknown-linux-gnu %s -### -o %t.o -no-integrated-as 2>&1 | FileCheck -check-prefix=CHECK_32_BE_AS_ARGS %s
+// CHECK_32_BE_AS_ARGS: "-mppc"
+// CHECK_32_BE_AS_ARGS-SAME: "-mbig-endian"
+// CHECK_32_BE_AS_ARGS-SAME: "-many"
+
+// RUN: %clang -target powerpcle-unknown-linux-gnu %s -### -o %t.o -no-integrated-as 2>&1 | FileCheck -check-prefix=CHECK_32_LE_AS_ARGS %s
+// CHECK_32_LE_AS_ARGS: "-mppc"
+// CHECK_32_LE_AS_ARGS-SAME: "-mlittle-endian"
+// CHECK_32_LE_AS_ARGS-SAME: "-many"
+
+// RUN: %clang -target powerpc64-unknown-linux-gnu %s -### -o %t.o -no-integrated-as 2>&1 | FileCheck -check-prefix=CHECK_64_BE_AS_ARGS %s
+// CHECK_64_BE_AS_ARGS: "-mppc64"
+// CHECK_64_BE_AS_ARGS-SAME: "-mbig-endian"
+// CHECK_64_BE_AS_ARGS-SAME: "-many"
+
+// RUN: %clang -target powerpc64le-unknown-linux-gnu %s -### -o %t.o -no-integrated-as 2>&1 | FileCheck -check-prefix=CHECK_64_LE_AS_ARGS %s
+// CHECK_64_LE_AS_ARGS: "-mppc64"
+// CHECK_64_LE_AS_ARGS-SAME: "-mlittle-endian"
+// CHECK_64_LE_AS_ARGS-SAME: "-mpower8"
// OpenMP features
// RUN: %clang -target powerpc-unknown-linux-gnu %s -### -fopenmp=libomp -o %t.o 2>&1 | FileCheck -check-prefix=CHECK_OPENMP_TLS %s
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