From: Luke Cheeseman <luke.cheeseman@arm.com>
Date: Mon, 24 Sep 2018 16:36:33 +0000 (+0000)
Subject: Reverting r342895
X-Git-Tag: llvmorg-8.0.0-rc1~8082
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=3bdf34f20e9afa3e0c389b3e8df1d30503e77fa7;p=platform%2Fupstream%2Fllvm.git

Reverting r342895

- The used builtins do not compile for pre arm v8.3a targets with gcc

llvm-svn: 342901
---

diff --git a/libunwind/include/libunwind.h b/libunwind/include/libunwind.h
index d824c13..97d2b82 100644
--- a/libunwind/include/libunwind.h
+++ b/libunwind/include/libunwind.h
@@ -57,9 +57,6 @@ enum {
   UNW_EINVAL        = -6547, /* unsupported operation or bad value */
   UNW_EBADVERSION   = -6548, /* unwind info has unsupported version */
   UNW_ENOINFO       = -6549  /* no unwind info found */
-#if defined(_LIBUNWIND_TARGET_AARCH64) && !defined(_LIBUNWIND_IS_NATIVE_ONLY)
-  , UNW_ECROSSRASIGNING = -6550 /* cross unwind with return address signing */
-#endif
 };
 
 struct unw_context_t {
@@ -550,8 +547,6 @@ enum {
   UNW_ARM64_X31 = 31,
   UNW_ARM64_SP  = 31,
   // reserved block
-  UNW_ARM64_RA_SIGN_STATE = 34,
-  // reserved block
   UNW_ARM64_D0  = 64,
   UNW_ARM64_D1  = 65,
   UNW_ARM64_D2  = 66,
diff --git a/libunwind/src/DwarfInstructions.hpp b/libunwind/src/DwarfInstructions.hpp
index 6ccd860..88e6719 100644
--- a/libunwind/src/DwarfInstructions.hpp
+++ b/libunwind/src/DwarfInstructions.hpp
@@ -198,24 +198,6 @@ int DwarfInstructions<A, R>::stepWithDwarf(A &addressSpace, pint_t pc,
       // restoring SP means setting it to CFA.
       newRegisters.setSP(cfa);
 
-#if defined(_LIBUNWIND_TARGET_AARCH64)
-      // If the target is aarch64 then the return address may have been signed
-      // using the v8.3 pointer authentication extensions. The original
-      // return address needs to be authenticated before the return address is
-      // restored. autia1716 is used instead of autia as autia1716 assembles
-      // to a NOP on pre-v8.3a architectures.
-      if (prolog.savedRegisters[UNW_ARM64_RA_SIGN_STATE].value) {
-#if !defined(_LIBUNWIND_IS_NATIVE_ONLY)
-        return UNW_ECROSSRASIGNING;
-#else
-        register unsigned long long x17 __asm("x17") = returnAddress;
-        register unsigned long long x16 __asm("x16") = cfa;
-        asm("autia1716": "+r"(x17): "r"(x16));
-        returnAddress = x17;
-#endif
-      }
-#endif
-
       // Return address is address after call site instruction, so setting IP to
       // that does simualates a return.
       newRegisters.setIP(returnAddress);
diff --git a/libunwind/src/DwarfParser.hpp b/libunwind/src/DwarfParser.hpp
index 68506a3..b749b77 100644
--- a/libunwind/src/DwarfParser.hpp
+++ b/libunwind/src/DwarfParser.hpp
@@ -666,14 +666,6 @@ bool CFI_Parser<A>::parseInstructions(A &addressSpace, pint_t instructions,
       _LIBUNWIND_TRACE_DWARF(
           "DW_CFA_GNU_negative_offset_extended(%" PRId64 ")\n", offset);
       break;
-
-#if defined(_LIBUNWIND_TARGET_AARCH64)
-    case DW_CFA_AARCH64_negate_ra_state:
-      results->savedRegisters[UNW_ARM64_RA_SIGN_STATE].value ^= 0x1;
-      _LIBUNWIND_TRACE_DWARF("DW_CFA_AARCH64_negate_ra_state\n");
-      break;
-#endif
-
     default:
       operand = opcode & 0x3F;
       switch (opcode & 0xC0) {
diff --git a/libunwind/src/Registers.hpp b/libunwind/src/Registers.hpp
index 6584824..37ec84b 100644
--- a/libunwind/src/Registers.hpp
+++ b/libunwind/src/Registers.hpp
@@ -1786,7 +1786,7 @@ private:
     uint64_t __lr;    // Link register x30
     uint64_t __sp;    // Stack pointer x31
     uint64_t __pc;    // Program counter
-    uint64_t __ra_sign_state; // RA sign state register
+    uint64_t padding; // 16-byte align
   };
 
   GPRs    _registers;
@@ -1822,8 +1822,6 @@ inline bool Registers_arm64::validRegister(int regNum) const {
     return false;
   if (regNum > 95)
     return false;
-  if (regNum == UNW_ARM64_RA_SIGN_STATE)
-    return true;
   if ((regNum > 31) && (regNum < 64))
     return false;
   return true;
@@ -1834,11 +1832,8 @@ inline uint64_t Registers_arm64::getRegister(int regNum) const {
     return _registers.__pc;
   if (regNum == UNW_REG_SP)
     return _registers.__sp;
-  if (regNum == UNW_ARM64_RA_SIGN_STATE)
-    return _registers.__ra_sign_state;
   if ((regNum >= 0) && (regNum < 32))
     return _registers.__x[regNum];
-
   _LIBUNWIND_ABORT("unsupported arm64 register");
 }
 
@@ -1847,8 +1842,6 @@ inline void Registers_arm64::setRegister(int regNum, uint64_t value) {
     _registers.__pc = value;
   else if (regNum == UNW_REG_SP)
     _registers.__sp = value;
-  else if (regNum == UNW_ARM64_RA_SIGN_STATE)
-    _registers.__ra_sign_state = value;
   else if ((regNum >= 0) && (regNum < 32))
     _registers.__x[regNum] = value;
   else
diff --git a/libunwind/src/dwarf2.h b/libunwind/src/dwarf2.h
index 58525ee..0dcd2ca 100644
--- a/libunwind/src/dwarf2.h
+++ b/libunwind/src/dwarf2.h
@@ -49,10 +49,7 @@ enum {
   // GNU extensions
   DW_CFA_GNU_window_save              = 0x2D,
   DW_CFA_GNU_args_size                = 0x2E,
-  DW_CFA_GNU_negative_offset_extended = 0x2F,
-
-  // AARCH64 extensions
-  DW_CFA_AARCH64_negate_ra_state      = 0x2D
+  DW_CFA_GNU_negative_offset_extended = 0x2F
 };