[AArch64] Support the .inst directive for MachO and COFF targets

Contrary to ELF, we don't add any markers that distinguish data generated with .long from normal instructions, so the .inst directive only adds compatibility with assembly that uses it. Differential Revision: https://reviews.llvm.org/D49935 llvm-svn: 338355
llvm · Jul 31, 2018 · 3e3d39d · 3e3d39d
1 parent 2a6c842
commit 3e3d39d
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Showing 3 changed files with 60 additions and 7 deletions.
diff --git a/llvm/lib/Target/AArch64/AsmParser/AArch64AsmParser.cpp b/llvm/lib/Target/AArch64/AsmParser/AArch64AsmParser.cpp
@@ -4873,12 +4873,11 @@ bool AArch64AsmParser::ParseDirective(AsmToken DirectiveID) {
     parseDirectiveLtorg(Loc);
   else if (IDVal == ".unreq")
     parseDirectiveUnreq(Loc);
-  else if (!IsMachO && !IsCOFF) {
-    if (IDVal == ".inst")
-      parseDirectiveInst(Loc);
-    else
-      return true;
-  } else if (IDVal == MCLOHDirectiveName())
+  else if (IDVal == ".inst")
+    parseDirectiveInst(Loc);
+  else if (!IsMachO && !IsCOFF)
+    return true;
+  else if (IDVal == MCLOHDirectiveName())
     parseDirectiveLOH(IDVal, Loc);
   else
     return true;

diff --git a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64TargetStreamer.cpp b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64TargetStreamer.cpp
@@ -39,4 +39,16 @@ void AArch64TargetStreamer::emitCurrentConstantPool() {
 // finish() - write out any non-empty assembler constant pools.
 void AArch64TargetStreamer::finish() { ConstantPools->emitAll(Streamer); }
 
-void AArch64TargetStreamer::emitInst(uint32_t Inst) {}
+void AArch64TargetStreamer::emitInst(uint32_t Inst) {
+  char Buffer[4];
+
+  // We can't just use EmitIntValue here, as that will swap the
+  // endianness on big-endian systems (instructions are always
+  // little-endian).
+  for (unsigned I = 0; I < 4; ++I) {
+    Buffer[I] = uint8_t(Inst);
+    Inst >>= 8;
+  }
+
+  getStreamer().EmitBytes(StringRef(Buffer, 4));
+}
diff --git a/llvm/test/MC/AArch64/inst-directive-other.s b/llvm/test/MC/AArch64/inst-directive-other.s
@@ -0,0 +1,42 @@
+// RUN: llvm-mc %s -triple=arm64-apple-darwin -filetype=asm -o - \
+// RUN:   | FileCheck %s --check-prefix=CHECK-ASM
+// RUN: llvm-mc %s -triple=arm64-apple-darwin -filetype=obj -o - \
+// RUN:   | llvm-objdump -d - | FileCheck %s --check-prefixes=CHECK-OBJ,CHECK-OBJ-CODE
+// RUN: llvm-mc %s -triple=aarch64-win32-gnu -filetype=asm -o - \
+// RUN:   | FileCheck %s --check-prefix=CHECK-ASM
+// RUN: llvm-mc %s -triple=aarch64-win32-gnu -filetype=obj -o - \
+// RUN:   | llvm-objdump -d - | FileCheck %s --check-prefixes=CHECK-OBJ,CHECK-OBJ-CODE
+// RUN: llvm-mc %s -triple=aarch64-linux-gnu -filetype=asm -o - \
+// RUN:   | FileCheck %s --check-prefix=CHECK-ASM
+// RUN: llvm-mc %s -triple=aarch64-linux-gnu -filetype=obj -o - \
+// RUN:   | llvm-objdump -d - | FileCheck %s --check-prefixes=CHECK-OBJ,CHECK-OBJ-DATA
+// RUN: llvm-mc %s -triple=aarch64_be-linux-gnu -filetype=asm -o - \
+// RUN:   | FileCheck %s --check-prefix=CHECK-ASM
+// RUN: llvm-mc %s -triple=aarch64_be-linux-gnu -filetype=obj -o - \
+// RUN:   | llvm-objdump -d - | FileCheck %s --check-prefixes=CHECK-OBJ,CHECK-OBJ-BE
+
+    .text
+
+    .p2align  2
+    .globl _func
+_func:
+    nop
+    // A .long is stored differently for big endian aarch64 targets, while
+    // instructions always are stored in little endian.
+    // ELF distinguishes between data and code when emitted this way, but
+    // MachO and COFF don't.
+    .long 0xd503201f
+    .inst 0xd503201f
+
+// CHECK-ASM:        .p2align  2
+// CHECK-ASM:        .globl  _func
+// CHECK-ASM: _func:
+// CHECK-ASM:        nop
+// CHECK-ASM:        .{{long|word}}   3573751839
+// CHECK-ASM:        .inst   0xd503201f
+
+// CHECK-OBJ:        0:       1f 20 03 d5     nop
+// CHECK-OBJ-CODE:   4:       1f 20 03 d5     nop
+// CHECK-OBJ-DATA:   4:       1f 20 03 d5     .word 0xd503201f
+// CHECK-OBJ-BE:     4:       d5 03 20 1f     .word 0xd503201f
+// CHECK-OBJ:        8:       1f 20 03 d5     nop