8290780: AArch64: Crash in c2 nmethod running RunThese30M.java

Reviewed-by: dlong

Author: Andrew Haley

src/hotspot/cpu/aarch64/macroAssembler_aarch64.cpp

@@ -310,14 +310,12 @@ class Patcher : public RelocActions {
     ptrdiff_t offset = target - insn_addr;
     instructions = 2;
     precond(inner != nullptr);
-    uintptr_t dest = (uintptr_t)target;
+    // Give the inner reloc a chance to modify the target.
+    address adjusted_target = target;
+    instructions = (*inner)(insn_addr, adjusted_target);
     uintptr_t pc_page = (uintptr_t)insn_addr >> 12;
-    uintptr_t adr_page = (uintptr_t)target >> 12;
+    uintptr_t adr_page = (uintptr_t)adjusted_target >> 12;
     offset = adr_page - pc_page;
-    instructions = (*inner)(insn_addr, target);
-    // Now we extract the lower 21 bits of the signed offset field for
-    // the ADRP.
-    offset = offset << (64-21) >> (64-21);
     int offset_lo = offset & 3;
     offset >>= 2;
     Instruction_aarch64::spatch(insn_addr, 23, 5, offset);
@@ -340,8 +338,10 @@ class Patcher : public RelocActions {
     return 2;
   }
   static int adrpMovk_impl(address insn_addr, address &target) {
-    uintptr_t dest = (uintptr_t)target;
+    uintptr_t dest = uintptr_t(target);
     Instruction_aarch64::patch(insn_addr + sizeof (uint32_t), 20, 5, (uintptr_t)target >> 32);
+    dest = (dest & 0xffffffffULL) | (uintptr_t(insn_addr) & 0xffff00000000ULL);
+    target = address(dest);
     return 2;
   }
   virtual int immediate(address insn_addr, address &target) {
@@ -457,7 +457,7 @@ class Decoder : public RelocActions {
   static int adrpMovk_impl(address insn_addr, address &target) {
     uint32_t insn2 = insn_at(insn_addr, 1);
     uint64_t dest = uint64_t(target);
-    dest = (dest & 0xffffffff) |
+    dest = (dest & 0xffff0000ffffffff) |
       ((uint64_t)Instruction_aarch64::extract(insn2, 20, 5) << 32);
     target = address(dest);
 

src/hotspot/cpu/aarch64/stubGenerator_aarch64.cpp

@@ -6949,22 +6949,6 @@ class StubGenerator: public StubCodeGenerator {
 
     __ leave();
 
-#ifdef ASSERT
-    {
-      // Stress relocs for adrp() by trying to reach a page beyond
-      // the range of a simple ADRP instruction.
-      ExternalAddress longWayAway(__ pc() - (1ll << 34));
-      if (! __ is_valid_AArch64_address(longWayAway.target())) {
-        longWayAway = ExternalAddress(__ pc() + (1ll << 34));
-      }
-      if (__ is_valid_AArch64_address(longWayAway.target())) {
-        uint64_t offset;
-        __ adrp(rscratch1, longWayAway, offset);
-        __ add(rscratch1, rscratch1, offset);
-      }
-    }
-#endif // ASSERT
-
     // check for pending exceptions
 #ifdef ASSERT
     Label L;