Emit the build attribute Tag_conformance.

Claim conformance to version 2.09 of the ARM ABI.

This build attribute must be emitted first amongst the build attributes when
written to an object file. This is to simplify conformance detection by
consumers.

Change-Id: If9eddcfc416bc9ad6e5cc8cdcb05d0031af7657e

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225166 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/ARM/ARMAsmPrinter.cpp b/lib/Target/ARM/ARMAsmPrinter.cpp
index 0300f5875cac9bc0ed065e0c5e7e4a2068e5bed3..b17d4aa19f707f354b7e494ea135cf54c9907a69 100644 (file)
--- a/lib/Target/ARM/ARMAsmPrinter.cpp
+++ b/lib/Target/ARM/ARMAsmPrinter.cpp
@@ -629,6 +629,8 @@ void ARMAsmPrinter::emitAttributes() {
   MCTargetStreamer &TS = *OutStreamer.getTargetStreamer();
   ARMTargetStreamer &ATS = static_cast<ARMTargetStreamer &>(TS);
 
+  ATS.emitTextAttribute(ARMBuildAttrs::conformance, "2.09");
+
   ATS.switchVendor("aeabi");
 
   std::string CPUString = Subtarget->getCPUString();

diff --git a/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp b/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp
index e92a43c5b79b50488065a0153a116945858226a5..f9403063dd6f98df9cee3bea5ab4bbdc64c86cd2 100644 (file)
--- a/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp
+++ b/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp
@@ -300,7 +300,19 @@ private:
     StringRef StringValue;
 
     static bool LessTag(const AttributeItem &LHS, const AttributeItem &RHS) {
-      return (LHS.Tag < RHS.Tag);
+      // The conformance tag must be emitted first when serialised
+      // into an object file. Specifically, the addenda to the ARM ABI
+      // states that (2.3.7.4):
+      //
+      // "To simplify recognition by consumers in the common case of
+      // claiming conformity for the whole file, this tag should be
+      // emitted first in a file-scope sub-subsection of the first
+      // public subsection of the attributes section."
+      //
+      // So it is special-cased in this comparison predicate when the
+      // attributes are sorted in finishAttributeSection().
+      return (RHS.Tag != ARMBuildAttrs::conformance) &&
+             ((LHS.Tag == ARMBuildAttrs::conformance) || (LHS.Tag < RHS.Tag));
     }
   };
 

diff --git a/test/CodeGen/ARM/build-attributes.ll b/test/CodeGen/ARM/build-attributes.ll
index d017e066562a7742e13842e96129b222e08db7ab..3d1b2b7c8e062dbc08dbbd31c8cc8e2ad65a464a 100644 (file)
--- a/test/CodeGen/ARM/build-attributes.ll
+++ b/test/CodeGen/ARM/build-attributes.ll
@@ -279,6 +279,7 @@
 ; V7-FAST:   .eabi_attribute 23, 1
 
 ; V8:      .syntax unified
+; V8: .eabi_attribute 67, "2.09"
 ; V8: .eabi_attribute 6, 14
 ; V8-NOT:   .eabi_attribute 19
 ; V8: .eabi_attribute 20, 1

diff --git a/test/MC/ARM/directive-eabi_attribute.s b/test/MC/ARM/directive-eabi_attribute.s
index 135afa74f2f5a1478c5d826f831b299c42256052..ac7358f39d7c3133952dc526d5aeb03488722d02 100644 (file)
--- a/test/MC/ARM/directive-eabi_attribute.s
+++ b/test/MC/ARM/directive-eabi_attribute.s
@@ -5,6 +5,14 @@
         .syntax unified
         .thumb
 
+        .eabi_attribute Tag_conformance, "2.09"
+@ CHECK: .eabi_attribute 67, "2.09"
+@ Tag_conformance should be be emitted first in a file-scope
+@ sub-subsection of the first public subsection of the attributes
+@ section. 2.3.7.4 of ABI Addenda.
+@ CHECK-OBJ:        Tag: 67
+@ CHECK-OBJ-NEXT:   TagName: conformance
+@ CHECK-OBJ-NEXT:   Value: 2.09
        .eabi_attribute Tag_CPU_raw_name, "Cortex-A9"
 @ CHECK: .eabi_attribute 4, "Cortex-A9"
 @ CHECK-OBJ:        Tag: 4
@@ -220,11 +228,6 @@
 @ CHECK-OBJ-NEXT:   Value: 0
 @ CHECK-OBJ-NEXT:   TagName: T2EE_use
 @ CHECK-OBJ-NEXT:   Description: Not Permitted
-       .eabi_attribute Tag_conformance, "2.09"
-@ CHECK: .eabi_attribute 67, "2.09"
-@ CHECK-OBJ:        Tag: 67
-@ CHECK-OBJ-NEXT:   TagName: conformance
-@ CHECK-OBJ-NEXT:   Value: 2.09
        .eabi_attribute Tag_Virtualization_use, 0
 @ CHECK: .eabi_attribute 68, 0
 @ CHECK-OBJ:        Tag: 68

diff --git a/test/tools/llvm-readobj/ARM/attribute-conformance-1.s b/test/tools/llvm-readobj/ARM/attribute-conformance-1.s
new file mode 100644 (file)
index 0000000..daa44c1
--- /dev/null
+++ b/test/tools/llvm-readobj/ARM/attribute-conformance-1.s
@@ -0,0 +1,8 @@
+@ RUN: llvm-mc -triple armv7-elf -filetype asm -o - %s | FileCheck %s
+@ RUN: llvm-mc -triple armv7-eabi -filetype obj -o - %s \
+@ RUN:   | llvm-readobj -arm-attributes - | FileCheck %s --check-prefix=CHECK-OBJ
+.eabi_attribute  Tag_conformance, "0"
+@CHECK:   .eabi_attribute 67, "0"
+@CHECK-OBJ: Tag: 67
+@CHECK-OBJ-NEXT: TagName: conformance
+@CHECK-OBJ-NEXT: Value: 0

diff --git a/test/tools/llvm-readobj/ARM/attribute-conformance-2.s b/test/tools/llvm-readobj/ARM/attribute-conformance-2.s
new file mode 100644 (file)
index 0000000..47c83c0
--- /dev/null
+++ b/test/tools/llvm-readobj/ARM/attribute-conformance-2.s
@@ -0,0 +1,8 @@
+@ RUN: llvm-mc -triple armv7-elf -filetype asm -o - %s | FileCheck %s
+@ RUN: llvm-mc -triple armv7-eabi -filetype obj -o - %s \
+@ RUN:   | llvm-readobj -arm-attributes - | FileCheck %s --check-prefix=CHECK-OBJ
+.eabi_attribute  Tag_conformance, "A.long--non numeric oddity...!!"
+@CHECK:   .eabi_attribute 67, "A.long--non numeric oddity...!!"
+@CHECK-OBJ: Tag: 67
+@CHECK-OBJ-NEXT: TagName: conformance
+@CHECK-OBJ-NEXT: Value: A.long--non numeric oddity...!!