MIPS: fix build from IR files, nan2008 and FpAbi

[wzssyqa]

Summary

When we use llc or lld to compiler IR files, the features +nan2008 and +fpxx/+fp64 are not used.
Thus wrong format files are produced.

In IR files, the attributes are only set for function while not the whole compile units.
So we output .nan 2008 and .module fp=xx/64 before every function.

isFPXXDefault: for o32, the FPXX should always be the default, no matter about the vendors.
Of course some distributions with FP64 default enabled should be listed explicit.
Let's add them in future if we know about one.

[MaskRay]

test?

[wzssyqa]

Add llvm/test/CodeGen/Mips/abiflags-2008-fp64.ll

[MaskRay]

Rubber stamp. I try to find some mips folks who can verify, so maybe wait a day or so.

When we use llc or lld to compiler IR files, the features +nan2008 and +fpxx/+fp64 are not used. Thus wrong format files are produced.

Not sure lld is related. It just consumes the bitcode input when using LTO. Did you mean Clang?

llvm/lib/Target/Mips/MipsAsmPrinter.cpp

402–412

Seems that you can group TS/MTM declaration together, and then place TS. calls together?

llvm/test/CodeGen/Mips/abiflags-2008-fp64.ll

2

12

Delete unrelated attributes from the list.

[wzssyqa]

In D138179#3934543, @MaskRay wrote:

Rubber stamp. I try to find some mips folks who can verify, so maybe wait a day or so.

When we use llc or lld to compiler IR files, the features +nan2008 and +fpxx/+fp64 are not used. Thus wrong format files are produced.

Not sure lld is related. It just consumes the bitcode input when using LTO. Did you mean Clang?

Any program call libllvm to convert IR to asm file or object is effected.
the example is like this:

example 1:

clang -flto -mnan=2008 -O3 -target mipsel-linux-gnu -c test.c   # the nan2008 attribute does set
llc test.o  # the nan2008 is not set in the output test.o.s

example 2

clang -flto -mnan=2008 -O3 -target mipsel-linux-gnu -o a.out test.c
# the output is not nan2008 object
#due to clang doesn't pass -mllvm=-mattr=+nan2008 to lld.

For example2:
We can:

1. pass -mllvm=-mattr=+nan2008 to lld, while ld.bfd doesn't support it.
2. make lld/llvm can recognize the attributes #0 = in IR files.

[MaskRay]

llvm/lib/Target/Mips/MipsAsmPrinter.cpp

402–412

delete blank line

404

If ABI only used once, avoid the variable

[wzssyqa]

ahhh, ping.

[MaskRay]

(On a trip so I may be slow.)

I know very little about mips. I wish that some mips experts like @atanasyan can some proper checks but this patch seems fine.
Landing in one minute after testing finishes.

[nathanchance]

For what it's worth, this breaks building the Linux kernel's ARCH=mips 32r1_defconfig with clang and GNU as, with thousands of messages along the line of:

/tmp/mmc_ops-d329c3.s: Assembler messages:
/tmp/mmc_ops-d329c3.s:310: Error: .module is not permitted after generating code
/tmp/mmc_ops-d329c3.s:473: Error: .module is not permitted after generating code
/tmp/mmc_ops-d329c3.s:594: Error: .module is not permitted after generating code
/tmp/mmc_ops-d329c3.s:687: Error: .module is not permitted after generating code
/tmp/mmc_ops-d329c3.s:781: Error: .module is not permitted after generating code
/tmp/mmc_ops-d329c3.s:946: Error: .module is not permitted after generating code
/tmp/mmc_ops-d329c3.s:1023: Error: .module is not permitted after generating code
...

A simplified reproducer:

void rcu_normal_store() {}
void __attribute__ksysfs_init() {}

$ clang --version | head -1
ClangBuiltLinux clang version 16.0.0 (https://github.com/llvm/llvm-project 9739bb81aed490bfcbcbbac6970da8fb7232fd34)

$ clang --target=mips-linux-gnu -fno-integrated-as -c -o /dev/null ksysfs.i
/tmp/ksysfs-9b0c50.s: Assembler messages:
/tmp/ksysfs-9b0c50.s:44: Error: .module is not permitted after generating code
clang-16: error: assembler command failed with exit code 1 (use -v to see invocation)

$ clang --version | head -1
ClangBuiltLinux clang version 16.0.0 (https://github.com/llvm/llvm-project 92619956eb27ef08dd24045307593fc3d7f78db0)

$ clang --target=mips-linux-gnu -fno-integrated-as -c -o /dev/null ksysfs.i

[wzssyqa]

In D138179#4002068, @nathanchance wrote:

For what it's worth, this breaks building the Linux kernel's ARCH=mips 32r1_defconfig with clang and GNU as, with thousands of messages along the line of:

/tmp/mmc_ops-d329c3.s: Assembler messages:
/tmp/mmc_ops-d329c3.s:310: Error: .module is not permitted after generating code
/tmp/mmc_ops-d329c3.s:473: Error: .module is not permitted after generating code
/tmp/mmc_ops-d329c3.s:594: Error: .module is not permitted after generating code
/tmp/mmc_ops-d329c3.s:687: Error: .module is not permitted after generating code
/tmp/mmc_ops-d329c3.s:781: Error: .module is not permitted after generating code
/tmp/mmc_ops-d329c3.s:946: Error: .module is not permitted after generating code
/tmp/mmc_ops-d329c3.s:1023: Error: .module is not permitted after generating code
...

A simplified reproducer:

void rcu_normal_store() {}
void __attribute__ksysfs_init() {}

Thanks for your test. I will work it just now.

$ clang --version | head -1
ClangBuiltLinux clang version 16.0.0 (https://github.com/llvm/llvm-project 9739bb81aed490bfcbcbbac6970da8fb7232fd34)

$ clang --target=mips-linux-gnu -fno-integrated-as -c -o /dev/null ksysfs.i
/tmp/ksysfs-9b0c50.s: Assembler messages:
/tmp/ksysfs-9b0c50.s:44: Error: .module is not permitted after generating code
clang-16: error: assembler command failed with exit code 1 (use -v to see invocation)

$ clang --version | head -1
ClangBuiltLinux clang version 16.0.0 (https://github.com/llvm/llvm-project 92619956eb27ef08dd24045307593fc3d7f78db0)

$ clang --target=mips-linux-gnu -fno-integrated-as -c -o /dev/null ksysfs.i

In D138179#4002068, @nathanchance wrote:

For what it's worth, this breaks building the Linux kernel's ARCH=mips 32r1_defconfig with clang and GNU as, with thousands of messages along the line of:

/tmp/mmc_ops-d329c3.s: Assembler messages:
/tmp/mmc_ops-d329c3.s:310: Error: .module is not permitted after generating code
/tmp/mmc_ops-d329c3.s:473: Error: .module is not permitted after generating code
/tmp/mmc_ops-d329c3.s:594: Error: .module is not permitted after generating code
/tmp/mmc_ops-d329c3.s:687: Error: .module is not permitted after generating code
/tmp/mmc_ops-d329c3.s:781: Error: .module is not permitted after generating code
/tmp/mmc_ops-d329c3.s:946: Error: .module is not permitted after generating code
/tmp/mmc_ops-d329c3.s:1023: Error: .module is not permitted after generating code
...

A simplified reproducer:

void rcu_normal_store() {}
void __attribute__ksysfs_init() {}

$ clang --version | head -1
ClangBuiltLinux clang version 16.0.0 (https://github.com/llvm/llvm-project 9739bb81aed490bfcbcbbac6970da8fb7232fd34)

$ clang --target=mips-linux-gnu -fno-integrated-as -c -o /dev/null ksysfs.i
/tmp/ksysfs-9b0c50.s: Assembler messages:
/tmp/ksysfs-9b0c50.s:44: Error: .module is not permitted after generating code
clang-16: error: assembler command failed with exit code 1 (use -v to see invocation)

$ clang --version | head -1
ClangBuiltLinux clang version 16.0.0 (https://github.com/llvm/llvm-project 92619956eb27ef08dd24045307593fc3d7f78db0)

$ clang --target=mips-linux-gnu -fno-integrated-as -c -o /dev/null ksysfs.i

[wzssyqa]

https://reviews.llvm.org/D140270

clang/lib/Driver/ToolChains/Arch/Mips.cpp

bool mips::isFP64ADefault(const llvm::Triple &Triple, StringRef CPUName) {
   // Android MIPS32R6 defaults to FP64A.
   return llvm::StringSwitch<bool>(CPUName)
       .Case("mips32r6", true)
       .Default(false);
 }
 
 bool mips::isFPXXDefault(const llvm::Triple &Triple, StringRef CPUName,
                          StringRef ABIName, mips::FloatABI FloatABI) {
-  if (Triple.getVendor() != llvm::Triple::ImaginationTechnologies &&
-      Triple.getVendor() != llvm::Triple::MipsTechnologies &&
-      !Triple.isAndroid())
-    return false;
-
   if (ABIName != "32")
     return false;
 
   // FPXX shouldn't be used if either -msoft-float or -mfloat-abi=soft is
   // present.
   if (FloatABI == mips::FloatABI::Soft)
     return false;
 

clang/test/Driver/mips-as.c

 // RUN: %clang -target mips64-linux-gnu -mips64r6 -### \
 // RUN:   -no-integrated-as -fno-pic -c %s -fno-pic -mno-abicalls 2>&1 \
 // RUN:   | FileCheck -check-prefix=MIPS-ALIAS-64R6 %s
 // MIPS-ALIAS-64R6: as{{(.exe)?}}" "-march" "mips64r6" "-mabi" "64" "-mno-shared" "-EB"
 //
 // RUN: %clang -target mips-linux-gnu -mno-mips16 -mips16 -### \
 // RUN:   -no-integrated-as -fno-pic -c %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=MIPS-16 %s
-// MIPS-16: as{{(.exe)?}}" "-march" "mips32r2" "-mabi" "32" "-mno-shared" "-call_nonpic" "-EB" "-mips16"
+// MIPS-16: as{{(.exe)?}}" "-march" "mips32r2" "-mabi" "32" "-mno-shared" "-call_nonpic" "-EB" "-mfpxx" "-mips16"
 //
 // RUN: %clang -target mips-linux-gnu -mips16 -mno-mips16 -### \
 // RUN:   -no-integrated-as -fno-pic -c %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=MIPS-N16 %s
 // MIPS-N16: as{{(.exe)?}}"
 // MIPS-N16: -no-mips16
 //
 // RUN: %clang -target mips-linux-gnu -mno-micromips -mmicromips -### \
 // RUN:   -no-integrated-as -fno-pic -c %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=MIPS-MICRO %s
-// MIPS-MICRO: as{{(.exe)?}}" "-march" "mips32r2" "-mabi" "32" "-mno-shared" "-call_nonpic" "-EB" "-mmicromips"
+// MIPS-MICRO: as{{(.exe)?}}" "-march" "mips32r2" "-mabi" "32" "-mno-shared" "-call_nonpic" "-EB" "-mfpxx" "-mmicromips"
 //
 // RUN: %clang -target mips-linux-gnu -mmicromips -mno-micromips -### \
 // RUN:   -no-integrated-as -fno-pic -c %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=MIPS-NMICRO %s
 // MIPS-NMICRO: as{{(.exe)?}}"
 // MIPS-NMICRO-NOT: {{[A-Za-z\\\/]*}}as{{(.exe)?}}{{.*}}"-mmicromips"
 //
 // RUN: %clang -target mips-linux-gnu -mno-dsp -mdsp -### \
 // RUN:   -no-integrated-as -fno-pic -c %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=MIPS-DSP %s
-// MIPS-DSP: as{{(.exe)?}}" "-march" "mips32r2" "-mabi" "32" "-mno-shared" "-call_nonpic" "-EB" "-mdsp"
+// MIPS-DSP: as{{(.exe)?}}" "-march" "mips32r2" "-mabi" "32" "-mno-shared" "-call_nonpic" "-EB" "-mfpxx" "-mdsp"
 //
 // RUN: %clang -target mips-linux-gnu -mdsp -mno-dsp -### \
 // RUN:   -no-integrated-as -fno-pic -c %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=MIPS-NDSP %s
 // MIPS-NDSP: as{{(.exe)?}}"
 // MIPS-NDSP-NOT: "{{[ A-Za-z\\\/]*}}as{{(.exe)?}}{{.*}}"-mdsp"
 //
 // RUN: %clang -target mips-linux-gnu -mno-dspr2 -mdspr2 -### \
 // RUN:   -no-integrated-as -fno-pic -c %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=MIPS-DSPR2 %s
-// MIPS-DSPR2: as{{(.exe)?}}" "-march" "mips32r2" "-mabi" "32" "-mno-shared" "-call_nonpic" "-EB" "-mdspr2"
+// MIPS-DSPR2: as{{(.exe)?}}" "-march" "mips32r2" "-mabi" "32" "-mno-shared" "-call_nonpic" "-EB" "-mfpxx" "-mdspr2"
 //
 // RUN: %clang -target mips-linux-gnu -mdspr2 -mno-dspr2 -### \
 // RUN:   -no-integrated-as -fno-pic -c %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=MIPS-NDSPR2 %s
 // MIPS-NDSPR2: as{{(.exe)?}}"
 // MIPS-NDSPR2-NOT: "{{[ A-Za-z\\\/]*}}as{{(.exe)?}}{{.*}}"-mdspr2"
 //
 // RUN: %clang -target mips-linux-gnu -mnan=legacy -mnan=2008 -### \

 // RUN: %clang -target mips-linux-gnu -mfpxx -mfp32 -mfp64 -### \
 // RUN:   -no-integrated-as -fno-pic -c %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=MIPS-MFP64 %s
 // MIPS-MFP64: as{{(.exe)?}}" "-march" "mips32r2" "-mabi" "32" "-mno-shared" "-call_nonpic" "-EB" "-mfp64"
 //
 // RUN: %clang -target mips-linux-gnu -mno-msa -mmsa -### \
 // RUN:   -no-integrated-as -fno-pic -c %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=MIPS-MSA %s
-// MIPS-MSA: as{{(.exe)?}}" "-march" "mips32r2" "-mabi" "32" "-mno-shared" "-call_nonpic" "-EB" "-mmsa"
+// MIPS-MSA: as{{(.exe)?}}" "-march" "mips32r2" "-mabi" "32" "-mno-shared" "-call_nonpic" "-EB" "-mfpxx" "-mmsa"
 //
 // RUN: %clang -target mips-linux-gnu -mmsa -mno-msa -### \
 // RUN:   -no-integrated-as -fno-pic -c %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=MIPS-NMSA %s
 // MIPS-NMSA: as{{(.exe)?}}"
 // MIPS-NMSA-NOT: "{{[ A-Za-z\\\/]*}}as{{(.exe)?}}{{.*}}"-mmsa"
 //
 // We've already tested MIPS32r2 and MIPS64r2 thoroughly. Do minimal tests on

clang/test/Driver/mips-integrated-as.s

 // RUN: %clang -target mips-linux-gnu -### -fintegrated-as -c %s -mno-msa 2>&1 | \
 // RUN:   FileCheck -check-prefix=MSA-OFF %s
 // MSA-OFF: -cc1as
 // MSA-OFF: "-target-feature" "-msa"
 
 // RUN: %clang -target mips-linux-gnu -### -fintegrated-as -c %s 2>&1 | \
 // RUN:   FileCheck -check-prefix=FPXX-DEFAULT %s
 // FPXX-DEFAULT: -cc1as
-// FPXX-DEFAULT-NOT: "-target-feature" "+fpxx"
-// FPXX-DEFAULT-NOT: "-target-feature" "+nooddspreg"
+// FPXX-DEFAULT: "-target-feature" "+fpxx"
+// FPXX-DEFAULT: "-target-feature" "+nooddspreg"
 
 // RUN: %clang -target mips-linux-gnu -### -fintegrated-as -c %s -mfp32 2>&1 | \
 // RUN:   FileCheck -check-prefix=FP32 %s
 // FP32: -cc1as
 // FP32: "-target-feature" "-fp64"
 
 // RUN: %clang -target mips-linux-gnu -### -fintegrated-as -c %s -mfpxx 2>&1 | \
 // RUN:   FileCheck -check-prefix=FPXX %s
 // FPXX: -cc1as
 // FPXX: "-target-feature" "+fpxx"
 // FPXX: "-target-feature" "+nooddspreg"
 
 // RUN: %clang -target mips-linux-gnu -### -fintegrated-as -c %s -mfp64 2>&1 | \
 // RUN:   FileCheck -check-prefix=FP64 %s
 // FP64: -cc1as
 // FP64: "-target-feature" "+fp64"
 
 // RUN: %clang -target mips-linux-gnu -### -fintegrated-as -c %s 2>&1 | \
 // RUN:   FileCheck -check-prefix=ODDSPREG-DEFAULT %s
 // ODDSPREG-DEFAULT: -cc1as
-// ODDSPREG-DEFAULT-NOT: "-target-feature" "{{[+-]}}nooddspreg"
+// ODDSPREG-DEFAULT: "-target-feature" "+nooddspreg"
 
 // RUN: %clang -target mips-linux-gnu -### -fintegrated-as -c %s -modd-spreg 2>&1 | \
 // RUN:   FileCheck -check-prefix=ODDSPREG-ON %s
 // ODDSPREG-ON: -cc1as
 // ODDSPREG-ON: "-target-feature" "-nooddspreg"
 
 // RUN: %clang -target mips-linux-gnu -### -fintegrated-as -c %s -mno-odd-spreg 2>&1 | \
 // RUN:   FileCheck -check-prefix=ODDSPREG-OFF %s

llvm/lib/Target/Mips/MipsAsmPrinter.cpp

const char *MipsAsmPrinter::getCurrentABIString() const {
   case MipsABIInfo::ABI::N32:  return "abiN32";
   case MipsABIInfo::ABI::N64:  return "abi64";
   default: llvm_unreachable("Unknown Mips ABI");
   }
 }
 
 void MipsAsmPrinter::emitFunctionEntryLabel() {
   MipsTargetStreamer &TS = getTargetStreamer();
 
+  TS.updateABIInfo(*Subtarget);
+  if (Subtarget->isNaN2008())
+    TS.emitDirectiveNaN2008();
+  const MipsTargetMachine &MTM = static_cast<const MipsTargetMachine &>(TM);
+  const MipsABIInfo &ABI = MTM.getABI();
+
+  if ((ABI.IsO32() && (Subtarget->isABI_FPXX() || Subtarget->isFP64bit())) ||
+      Subtarget->useSoftFloat())
+    TS.emitDirectiveModuleFP();
+
   // NaCl sandboxing requires that indirect call instructions are masked.
   // This means that function entry points should be bundle-aligned.
   if (Subtarget->isTargetNaCl())
     emitAlignment(std::max(MF->getAlignment(), MIPS_NACL_BUNDLE_ALIGN));
 
   if (Subtarget->inMicroMipsMode()) {
     TS.emitDirectiveSetMicroMips();
     TS.setUsesMicroMips();

llvm/test/CodeGen/Mips/abiflags-2008-fp64.ll

+; RUN: llc %s -o - | FileCheck %s
+
+target triple = "mipsel-unknown-linux-gnu"
+
+define dso_local void @test() #0 {
+  ret void
+}
+
+attributes #0 = { "target-cpu"="mips32r2" "target-features"="+fp64,+mips32r2,+nan2008" }
+
+
+; CHECK: .nan    2008
+; CHECK: .module fp=64