Revert "Revert "Store resolved Strings for AOT code in .bss.""

Fixed oat_test to keep dex files alive. Fixed mips build.
Rewritten the .bss GC root visiting and added write barrier
to the artResolveStringFromCode().

Test: build aosp_mips-eng
Test: m ART_DEFAULT_GC_TYPE=SS test-art-target-host-gtest-oat_test
Test: Run ART test suite on host and Nexus 9.
Bug: 20323084
Bug: 30627598

This reverts commit 5f926055cb88089d8ca27243f35a9dfd89d981f0.

Change-Id: I07fa2278d82b8eb64964c9a4b66cb93726ccda6b

1 files changed, 27 insertions, 49 deletions

diff --git a/compiler/utils/arm/assembler_thumb2.cc b/compiler/utils/arm/assembler_thumb2.cc
index 2269ba2d20..61b7f08518 100644
--- a/compiler/utils/arm/assembler_thumb2.cc
+++ b/compiler/utils/arm/assembler_thumb2.cc
@@ -2461,58 +2461,36 @@ void Thumb2Assembler::EmitLoadStore(Condition cond,
     }
   } else {
     // Register shift.
-    if (ad.GetRegister() == PC) {
-       // PC relative literal encoding.
-      int32_t offset = ad.GetOffset();
-      if (must_be_32bit || offset < 0 || offset >= (1 << 10) || !load) {
-        int32_t up = B23;
-        if (offset < 0) {
-          offset = -offset;
-          up = 0;
-        }
-        CHECK_LT(offset, (1 << 12));
-        int32_t encoding = 0x1f << 27 | 0xf << 16 | B22 | (load ? B20 : 0) |
-            offset | up |
-            static_cast<uint32_t>(rd) << 12;
-        Emit32(encoding);
-      } else {
-        // 16 bit literal load.
-        CHECK_GE(offset, 0);
-        CHECK_LT(offset, (1 << 10));
-        int32_t encoding = B14 | (load ? B11 : 0) | static_cast<uint32_t>(rd) << 8 | offset >> 2;
-        Emit16(encoding);
+    CHECK_NE(ad.GetRegister(), PC);
+    if (ad.GetShiftCount() != 0) {
+      // If there is a shift count this must be 32 bit.
+      must_be_32bit = true;
+    } else if (IsHighRegister(ad.GetRegisterOffset())) {
+      must_be_32bit = true;
+    }
+
+    if (must_be_32bit) {
+      int32_t encoding = 0x1f << 27 | (load ? B20 : 0) | static_cast<uint32_t>(rd) << 12 |
+          ad.encodingThumb(true);
+      if (half) {
+        encoding |= B21;
+      } else if (!byte) {
+        encoding |= B22;
       }
-    } else {
-      if (ad.GetShiftCount() != 0) {
-        // If there is a shift count this must be 32 bit.
-        must_be_32bit = true;
-      } else if (IsHighRegister(ad.GetRegisterOffset())) {
-        must_be_32bit = true;
+      if (load && is_signed && (byte || half)) {
+        encoding |= B24;
       }
-
-      if (must_be_32bit) {
-        int32_t encoding = 0x1f << 27 | (load ? B20 : 0) | static_cast<uint32_t>(rd) << 12 |
-            ad.encodingThumb(true);
-        if (half) {
-          encoding |= B21;
-        } else if (!byte) {
-          encoding |= B22;
-        }
-        if (load && is_signed && (byte || half)) {
-          encoding |= B24;
-        }
-        Emit32(encoding);
-      } else {
-        // 16 bit register offset.
-        int32_t encoding = B14 | B12 | (load ? B11 : 0) | static_cast<uint32_t>(rd) |
-            ad.encodingThumb(false);
-        if (byte) {
-          encoding |= B10;
-        } else if (half) {
-          encoding |= B9;
-        }
-        Emit16(encoding);
+      Emit32(encoding);
+    } else {
+      // 16 bit register offset.
+      int32_t encoding = B14 | B12 | (load ? B11 : 0) | static_cast<uint32_t>(rd) |
+          ad.encodingThumb(false);
+      if (byte) {
+        encoding |= B10;
+      } else if (half) {
+        encoding |= B9;
       }
+      Emit16(encoding);
     }
   }
 }