[ARM] Create SubtargetFeatures from build attrs

An ELFObjectFile can now create SubtargetFeatures from the available
ARM build attributes, in a similar manner to MIPS. I've moved the
MIPS code into its own function and the ARM handler also has a
separate function.

Differential Revision: https://reviews.llvm.org/D28291



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292403 91177308-0d34-0410-b5e6-96231b3b80d8

10 files changed, 322 insertions, 42 deletions

diff --git a/include/llvm/Object/ELFObjectFile.h b/include/llvm/Object/ELFObjectFile.h
index 452b45835a6..f9fdcac8c55 100644
--- a/include/llvm/Object/ELFObjectFile.h
+++ b/include/llvm/Object/ELFObjectFile.h
@@ -74,6 +74,10 @@ public:
 
   SubtargetFeatures getFeatures() const override;
 
+  SubtargetFeatures getMIPSFeatures() const override;
+
+  SubtargetFeatures getARMFeatures() const override;
+
   void setARMSubArch(Triple &TheTriple) const override;
 };
 
diff --git a/include/llvm/Object/ObjectFile.h b/include/llvm/Object/ObjectFile.h
index b689dc2ac03..b4251193cd1 100644
--- a/include/llvm/Object/ObjectFile.h
+++ b/include/llvm/Object/ObjectFile.h
@@ -267,6 +267,8 @@ public:
   virtual StringRef getFileFormatName() const = 0;
   virtual /* Triple::ArchType */ unsigned getArch() const = 0;
   virtual SubtargetFeatures getFeatures() const = 0;
+  virtual SubtargetFeatures getMIPSFeatures() const { return SubtargetFeatures(); }
+  virtual SubtargetFeatures getARMFeatures() const { return SubtargetFeatures(); }
   virtual void setARMSubArch(Triple &TheTriple) const { }
 
   /// Returns platform-specific object flags, if any.
diff --git a/lib/Object/ELFObjectFile.cpp b/lib/Object/ELFObjectFile.cpp
index fb133c254d0..3f8c81c8e91 100644
--- a/lib/Object/ELFObjectFile.cpp
+++ b/lib/Object/ELFObjectFile.cpp
@@ -12,6 +12,8 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Object/ELFObjectFile.h"
+#include "llvm/Support/ARMBuildAttributes.h"
+#include "llvm/Support/ARMAttributeParser.h"
 #include "llvm/Support/MathExtras.h"
 
 namespace llvm {
@@ -55,68 +57,177 @@ ObjectFile::createELFObjectFile(MemoryBufferRef Obj) {
   return std::move(R);
 }
 
-SubtargetFeatures ELFObjectFileBase::getFeatures() const {
-  switch (getEMachine()) {
-  case ELF::EM_MIPS: {
-    SubtargetFeatures Features;
-    unsigned PlatformFlags;
-    getPlatformFlags(PlatformFlags);
+SubtargetFeatures ELFObjectFileBase::getMIPSFeatures() const {
+  SubtargetFeatures Features;
+  unsigned PlatformFlags;
+  getPlatformFlags(PlatformFlags);
+
+  switch (PlatformFlags & ELF::EF_MIPS_ARCH) {
+  case ELF::EF_MIPS_ARCH_1:
+    break;
+  case ELF::EF_MIPS_ARCH_2:
+    Features.AddFeature("mips2");
+    break;
+  case ELF::EF_MIPS_ARCH_3:
+    Features.AddFeature("mips3");
+    break;
+  case ELF::EF_MIPS_ARCH_4:
+    Features.AddFeature("mips4");
+    break;
+  case ELF::EF_MIPS_ARCH_5:
+    Features.AddFeature("mips5");
+    break;
+  case ELF::EF_MIPS_ARCH_32:
+    Features.AddFeature("mips32");
+    break;
+  case ELF::EF_MIPS_ARCH_64:
+    Features.AddFeature("mips64");
+    break;
+  case ELF::EF_MIPS_ARCH_32R2:
+    Features.AddFeature("mips32r2");
+    break;
+  case ELF::EF_MIPS_ARCH_64R2:
+    Features.AddFeature("mips64r2");
+    break;
+  case ELF::EF_MIPS_ARCH_32R6:
+    Features.AddFeature("mips32r6");
+    break;
+  case ELF::EF_MIPS_ARCH_64R6:
+    Features.AddFeature("mips64r6");
+    break;
+  default:
+    llvm_unreachable("Unknown EF_MIPS_ARCH value");
+  }
+
+  switch (PlatformFlags & ELF::EF_MIPS_MACH) {
+  case ELF::EF_MIPS_MACH_NONE:
+    // No feature associated with this value.
+    break;
+  case ELF::EF_MIPS_MACH_OCTEON:
+    Features.AddFeature("cnmips");
+    break;
+  default:
+    llvm_unreachable("Unknown EF_MIPS_ARCH value");
+  }
+
+  if (PlatformFlags & ELF::EF_MIPS_ARCH_ASE_M16)
+    Features.AddFeature("mips16");
+  if (PlatformFlags & ELF::EF_MIPS_MICROMIPS)
+    Features.AddFeature("micromips");
+
+  return Features;
+}
 
-    switch (PlatformFlags & ELF::EF_MIPS_ARCH) {
-    case ELF::EF_MIPS_ARCH_1:
+SubtargetFeatures ELFObjectFileBase::getARMFeatures() const {
+  SubtargetFeatures Features;
+  ARMAttributeParser Attributes;
+  std::error_code EC = getBuildAttributes(Attributes);
+  if (EC)
+    return SubtargetFeatures();
+
+  // both ARMv7-M and R have to support thumb hardware div
+  bool isV7 = false;
+  if (Attributes.hasAttribute(ARMBuildAttrs::CPU_arch))
+    isV7 = Attributes.getAttributeValue(ARMBuildAttrs::CPU_arch)
+      == ARMBuildAttrs::v7;
+
+  if (Attributes.hasAttribute(ARMBuildAttrs::CPU_arch_profile)) {
+    switch(Attributes.getAttributeValue(ARMBuildAttrs::CPU_arch_profile)) {
+    case ARMBuildAttrs::ApplicationProfile:
+      Features.AddFeature("aclass");
       break;
-    case ELF::EF_MIPS_ARCH_2:
-      Features.AddFeature("mips2");
+    case ARMBuildAttrs::RealTimeProfile:
+      Features.AddFeature("rclass");
+      if (isV7)
+        Features.AddFeature("hwdiv");
       break;
-    case ELF::EF_MIPS_ARCH_3:
-      Features.AddFeature("mips3");
+    case ARMBuildAttrs::MicroControllerProfile:
+      Features.AddFeature("mclass");
+      if (isV7)
+        Features.AddFeature("hwdiv");
       break;
-    case ELF::EF_MIPS_ARCH_4:
-      Features.AddFeature("mips4");
+    }
+  }
+
+  if (Attributes.hasAttribute(ARMBuildAttrs::THUMB_ISA_use)) {
+    switch(Attributes.getAttributeValue(ARMBuildAttrs::THUMB_ISA_use)) {
+    default:
       break;
-    case ELF::EF_MIPS_ARCH_5:
-      Features.AddFeature("mips5");
+    case ARMBuildAttrs::Not_Allowed:
+      Features.AddFeature("thumb", false);
+      Features.AddFeature("thumb2", false);
       break;
-    case ELF::EF_MIPS_ARCH_32:
-      Features.AddFeature("mips32");
+    case ARMBuildAttrs::AllowThumb32:
+      Features.AddFeature("thumb2");
       break;
-    case ELF::EF_MIPS_ARCH_64:
-      Features.AddFeature("mips64");
+    }
+  }
+
+  if (Attributes.hasAttribute(ARMBuildAttrs::FP_arch)) {
+    switch(Attributes.getAttributeValue(ARMBuildAttrs::FP_arch)) {
+    default:
       break;
-    case ELF::EF_MIPS_ARCH_32R2:
-      Features.AddFeature("mips32r2");
+    case ARMBuildAttrs::Not_Allowed:
+      Features.AddFeature("vfp2", false);
+      Features.AddFeature("vfp3", false);
+      Features.AddFeature("vfp4", false);
       break;
-    case ELF::EF_MIPS_ARCH_64R2:
-      Features.AddFeature("mips64r2");
+    case ARMBuildAttrs::AllowFPv2:
+      Features.AddFeature("vfp2");
       break;
-    case ELF::EF_MIPS_ARCH_32R6:
-      Features.AddFeature("mips32r6");
+    case ARMBuildAttrs::AllowFPv3A:
+    case ARMBuildAttrs::AllowFPv3B:
+      Features.AddFeature("vfp3");
       break;
-    case ELF::EF_MIPS_ARCH_64R6:
-      Features.AddFeature("mips64r6");
+    case ARMBuildAttrs::AllowFPv4A:
+    case ARMBuildAttrs::AllowFPv4B:
+      Features.AddFeature("vfp4");
       break;
-    default:
-      llvm_unreachable("Unknown EF_MIPS_ARCH value");
     }
+  }
 
-    switch (PlatformFlags & ELF::EF_MIPS_MACH) {
-    case ELF::EF_MIPS_MACH_NONE:
-      // No feature associated with this value.
+  if (Attributes.hasAttribute(ARMBuildAttrs::Advanced_SIMD_arch)) {
+    switch(Attributes.getAttributeValue(ARMBuildAttrs::Advanced_SIMD_arch)) {
+    default:
+      break;
+    case ARMBuildAttrs::Not_Allowed:
+      Features.AddFeature("neon", false);
+      Features.AddFeature("fp16", false);
       break;
-    case ELF::EF_MIPS_MACH_OCTEON:
-      Features.AddFeature("cnmips");
+    case ARMBuildAttrs::AllowNeon:
+      Features.AddFeature("neon");
       break;
+    case ARMBuildAttrs::AllowNeon2:
+      Features.AddFeature("neon");
+      Features.AddFeature("fp16");
+      break;
+    }
+  }
+
+  if (Attributes.hasAttribute(ARMBuildAttrs::DIV_use)) {
+    switch(Attributes.getAttributeValue(ARMBuildAttrs::DIV_use)) {
     default:
-      llvm_unreachable("Unknown EF_MIPS_ARCH value");
+      break;
+    case ARMBuildAttrs::DisallowDIV:
+      Features.AddFeature("hwdiv", false);
+      Features.AddFeature("hwdiv-arm", false);
+      break;
+    case ARMBuildAttrs::AllowDIVExt:
+      Features.AddFeature("hwdiv");
+      Features.AddFeature("hwdiv-arm");
+      break;
     }
+  }
 
-    if (PlatformFlags & ELF::EF_MIPS_ARCH_ASE_M16)
-      Features.AddFeature("mips16");
-    if (PlatformFlags & ELF::EF_MIPS_MICROMIPS)
-      Features.AddFeature("micromips");
+  return Features;
+}
 
-    return Features;
-  }
+SubtargetFeatures ELFObjectFileBase::getFeatures() const {
+  switch (getEMachine()) {
+  case ELF::EM_MIPS:
+    return getMIPSFeatures();
+  case ELF::EM_ARM:
+    return getARMFeatures();
   default:
     return SubtargetFeatures();
   }
diff --git a/test/tools/llvm-objdump/ARM/v6-neg-subfeatures.s b/test/tools/llvm-objdump/ARM/v6-neg-subfeatures.s
new file mode 100644
index 00000000000..1a8d8f28333
--- /dev/null
+++ b/test/tools/llvm-objdump/ARM/v6-neg-subfeatures.s
@@ -0,0 +1,10 @@
+@ RUN: llvm-mc < %s -triple armv6 -mattr=+vfp2 -filetype=obj | llvm-objdump -triple=arm -d - | FileCheck %s
+
+.eabi_attribute Tag_FP_arch, 1 // VFP2
+
+vfp2:
+  vadd.f32 s0, s1, s2
+
+@CHECK-LABEL: vfp2
+@CHECK-NOT: 81 0a 30 ee vadd.f32 s0, s1, s2
+@CHECK: unknown
diff --git a/test/tools/llvm-objdump/ARM/v6-subfeatures.s b/test/tools/llvm-objdump/ARM/v6-subfeatures.s
new file mode 100644
index 00000000000..e8e806740d1
--- /dev/null
+++ b/test/tools/llvm-objdump/ARM/v6-subfeatures.s
@@ -0,0 +1,9 @@
+@ RUN: llvm-mc < %s -triple armv6 -mattr=+vfp2 -filetype=obj | llvm-objdump -triple=arm -d - | FileCheck %s
+
+.eabi_attribute Tag_FP_arch, 2 // VFP2
+
+vfp2:
+  vadd.f32 s0, s1, s2
+
+@CHECK-LABEL: vfp2
+@CHECK: 81 0a 30 ee vadd.f32 s0, s1, s2
diff --git a/test/tools/llvm-objdump/ARM/v7a-neg-subfeature.s b/test/tools/llvm-objdump/ARM/v7a-neg-subfeature.s
new file mode 100644
index 00000000000..8083e5b0eee
--- /dev/null
+++ b/test/tools/llvm-objdump/ARM/v7a-neg-subfeature.s
@@ -0,0 +1,44 @@
+@ RUN: llvm-mc < %s -triple armv7a -mattr=+vfp3,+neon,+fp16,+hwdiv-arm,+hwdiv -filetype=obj | llvm-objdump -triple=arm -d - | FileCheck %s
+@ RUN: llvm-mc < %s -triple armv7a -mattr=+vfp3,+neon,+fp16,+hwdiv-arm,+hwdiv -filetype=obj | llvm-objdump -triple=thumb -d - | FileCheck %s --check-prefix=CHECK-THUMB
+
+.eabi_attribute Tag_FP_arch, 0 // disallow vfp
+
+vfp2:
+  vmla.f32 s0, s1, s2
+
+@CHECK-LABEL: vfp2
+@CHECK-NOT: 81 0a 00 ee vmla.f32 s0, s1, s2
+@CHECK: unknown
+
+vfp3:
+  vmov.f32 s0, #0.5
+
+@CHECK-LABEL: vfp3
+@CHECK-NOT: 00 0a b6 ee vmov.f32 s0, #5.000000e-01
+
+neon:
+  vmla.f32 d0, d1, d2
+
+@CHECK-LABEL: neon
+@CHECK-NOT: 12 0d 01 f2 vmla.f32 d0, d1, d2
+@CHECK: unknown
+
+fp16:
+  vcvt.f32.f16 q0, d2
+
+@CHECK-LABEL: fp16
+@CHECK-NOT: 02 07 b6 f3  vcvt.f32.f16 q0, d2
+
+div_arm:
+  udiv r0, r1, r2
+
+@CHECK-LABEL: div_arm
+@CHECK-NOT: 11 f2 30 e7 udiv r0, r1, r2
+@CHECK: unknown
+
+.thumb
+div_thumb:
+  udiv r0, r1, r2
+
+@CHECK-LABEL: div_thumb
+@CHECK-THUMB-NOT: b1 fb f2 f0 udiv r0, r1, r2
diff --git a/test/tools/llvm-objdump/ARM/v7a-subfeature.s b/test/tools/llvm-objdump/ARM/v7a-subfeature.s
new file mode 100644
index 00000000000..f43554579a3
--- /dev/null
+++ b/test/tools/llvm-objdump/ARM/v7a-subfeature.s
@@ -0,0 +1,36 @@
+@ RUN: llvm-mc < %s -triple armv7a -mattr=+vfp3,+neon,+fp16,+hwdiv-arm -filetype=obj | llvm-objdump -triple=arm -d - | FileCheck %s
+
+.eabi_attribute Tag_FP_arch, 3 // VFP3
+.eabi_attribute Tag_Advanced_SIMD_arch, 2 // SIMDv1 with fp16
+.eabi_attribute Tag_DIV_use, 2 // permitted
+
+vfp2:
+  vmla.f32 s0, s1, s2
+
+@CHECK-LABEL: vfp2
+@CHECK: 81 0a 00 ee vmla.f32 s0, s1, s2
+
+vfp3:
+  vmov.f32 s0, #0.5
+
+@CHECK-LABEL: vfp3
+@CHECK: 00 0a b6 ee vmov.f32 s0, #5.000000e-01
+
+neon:
+  vmla.f32 d0, d1, d2
+
+@CHECK-LABEL: neon
+@CHECK: 12 0d 01 f2 vmla.f32 d0, d1, d2
+
+fp16:
+  vcvt.f32.f16 q0, d2
+
+@CHECK-LABEL: fp16
+@CHECK: 02 07 b6 f3  vcvt.f32.f16 q0, d2
+
+div:
+  udiv r0, r1, r2
+
+@CHECK-LABEL: div
+@CHECK: 11 f2 30 e7 udiv r0, r1, r2
+
diff --git a/test/tools/llvm-objdump/ARM/v7m-neg-subfeatures.s b/test/tools/llvm-objdump/ARM/v7m-neg-subfeatures.s
new file mode 100644
index 00000000000..b3a79c7d5c2
--- /dev/null
+++ b/test/tools/llvm-objdump/ARM/v7m-neg-subfeatures.s
@@ -0,0 +1,18 @@
+@ RUN: llvm-mc < %s -triple armv7m -mattr=+vfp4 -filetype=obj | llvm-objdump -triple=thumb -d - | FileCheck %s
+
+.eabi_attribute Tag_CPU_arch, 10 // v7
+.eabi_attribute Tag_FP_arch, 0 // VFP4
+
+.thumb
+vfp2:
+  vmla.f32 s0, s1, s2
+
+@CHECK-LABEL: vfp2
+@CHECK-NOT: 00 ee 81 0a vmla.f32 s0, s1, s2
+
+.thumb
+vfp4:
+  vmov.f32 s0, #0.5
+
+@CHECK-LABEL:vfp4
+@CHECK-NOT: b6 ee 00 0a vmov.f32 s0, #5.000000e-01
diff --git a/test/tools/llvm-objdump/ARM/v7m-subfeatures.s b/test/tools/llvm-objdump/ARM/v7m-subfeatures.s
new file mode 100644
index 00000000000..c7a40af8ae9
--- /dev/null
+++ b/test/tools/llvm-objdump/ARM/v7m-subfeatures.s
@@ -0,0 +1,26 @@
+@ RUN: llvm-mc < %s -triple armv7m -mattr=+vfp4 -filetype=obj | llvm-objdump -triple=thumb -d - | FileCheck %s
+
+.eabi_attribute Tag_CPU_arch, 10 // v7
+.eabi_attribute Tag_CPU_arch_profile, 0x4D // 'M' profile
+.eabi_attribute Tag_FP_arch, 5 // VFP4
+
+.thumb
+vfp2:
+  vmla.f32 s0, s1, s2
+
+@CHECK-LABEL: vfp2
+@CHECK: 00 ee 81 0a vmla.f32 s0, s1, s2
+
+.thumb
+vfp4:
+  vmov.f32 s0, #0.5
+
+@CHECK-LABEL: vfp4
+@CHECK: b6 ee 00 0a vmov.f32 s0, #5.000000e-01
+
+.thumb
+div:
+  udiv r0, r1, r2
+
+@CHECK-LABEL: div
+@CHECK: b1 fb f2 f0 udiv r0, r1, r2
diff --git a/test/tools/llvm-objdump/ARM/v7r-subfeatures.s b/test/tools/llvm-objdump/ARM/v7r-subfeatures.s
new file mode 100644
index 00000000000..bbe40a19387
--- /dev/null
+++ b/test/tools/llvm-objdump/ARM/v7r-subfeatures.s
@@ -0,0 +1,20 @@
+@ RUN: llvm-mc < %s -triple armv7r -mattr=+hwdiv-arm -filetype=obj | llvm-objdump -triple=thumb -d - | FileCheck %s
+@ RUN: llvm-mc < %s -triple armv7r -mattr=+hwdiv-arm -filetype=obj | llvm-objdump -triple=arm -d - | FileCheck %s --check-prefix=CHECK-ARM
+
+.eabi_attribute Tag_CPU_arch, 10 // v7
+.eabi_attribute Tag_CPU_arch_profile, 0x52 // 'R' profile
+
+.arm
+div_arm:
+  udiv r0, r1, r2
+
+@CHECK-LABEL: div_arm
+@CHECK-NOT: udiv r0, r1, r2
+@CHECK-ARM-NOT: udiv r0, r1, r2
+
+.thumb
+div_thumb:
+  udiv r0, r1, r2
+
+@CHECK-LABEL: div_thumb
+@CHECK: b1 fb f2 f0 udiv r0, r1, r2