Revert "ARM64: toHalf() intrinsic for ARMv8"

This reverts commit 2cc0c0f4b6a76dfb1ad205cfd79efe7efe2904d6.

Reason for revert: Broke some builds. To be investigated.

Bug: 143205070
Change-Id: Ib36e149cc5ed7f53c932c0b611b43c28d19f22dc
diff --git a/compiler/optimizing/intrinsics_arm64.cc b/compiler/optimizing/intrinsics_arm64.cc
index 6a666c9..185d487 100644
--- a/compiler/optimizing/intrinsics_arm64.cc
+++ b/compiler/optimizing/intrinsics_arm64.cc
@@ -3216,30 +3216,6 @@
   __ Fcvt(out, half);
 }
 
-void IntrinsicLocationsBuilderARM64::VisitFP16ToHalf(HInvoke* invoke) {
-  if (!codegen_->GetInstructionSetFeatures().HasFP16()) {
-    return;
-  }
-
-  LocationSummary* locations = new (allocator_) LocationSummary(invoke,
-                                                                LocationSummary::kNoCall,
-                                                                kIntrinsified);
-  locations->SetInAt(0, Location::RequiresFpuRegister());
-  locations->SetOut(Location::RequiresRegister());
-}
-
-void IntrinsicCodeGeneratorARM64::VisitFP16ToHalf(HInvoke* invoke) {
-  DCHECK(codegen_->GetInstructionSetFeatures().HasFP16());
-  MacroAssembler* masm = GetVIXLAssembler();
-  UseScratchRegisterScope scratch_scope(masm);
-  FPRegister in = SRegisterFrom(invoke->GetLocations()->InAt(0));
-  FPRegister half = scratch_scope.AcquireH();
-  Register out = WRegisterFrom(invoke->GetLocations()->Out());
-  __ Fcvt(half, in);
-  __ Fmov(out, half);
-  __ Sxth(out, out);  // sign extend due to returning a short type.
-}
-
 UNIMPLEMENTED_INTRINSIC(ARM64, ReferenceGetReferent)
 
 UNIMPLEMENTED_INTRINSIC(ARM64, StringStringIndexOf);
diff --git a/compiler/optimizing/intrinsics_arm_vixl.cc b/compiler/optimizing/intrinsics_arm_vixl.cc
index 74e861f..65f3888 100644
--- a/compiler/optimizing/intrinsics_arm_vixl.cc
+++ b/compiler/optimizing/intrinsics_arm_vixl.cc
@@ -3071,7 +3071,6 @@
 UNIMPLEMENTED_INTRINSIC(ARMVIXL, CRC32UpdateBytes)
 UNIMPLEMENTED_INTRINSIC(ARMVIXL, CRC32UpdateByteBuffer)
 UNIMPLEMENTED_INTRINSIC(ARMVIXL, FP16ToFloat)
-UNIMPLEMENTED_INTRINSIC(ARMVIXL, FP16ToHalf)
 
 UNIMPLEMENTED_INTRINSIC(ARMVIXL, StringStringIndexOf);
 UNIMPLEMENTED_INTRINSIC(ARMVIXL, StringStringIndexOfAfter);
diff --git a/compiler/optimizing/intrinsics_mips.cc b/compiler/optimizing/intrinsics_mips.cc
index b18bbdd..f71d281 100644
--- a/compiler/optimizing/intrinsics_mips.cc
+++ b/compiler/optimizing/intrinsics_mips.cc
@@ -2708,7 +2708,6 @@
 UNIMPLEMENTED_INTRINSIC(MIPS, CRC32UpdateBytes)
 UNIMPLEMENTED_INTRINSIC(MIPS, CRC32UpdateByteBuffer)
 UNIMPLEMENTED_INTRINSIC(MIPS, FP16ToFloat)
-UNIMPLEMENTED_INTRINSIC(MIPS, FP16ToHalf)
 
 UNIMPLEMENTED_INTRINSIC(MIPS, StringStringIndexOf);
 UNIMPLEMENTED_INTRINSIC(MIPS, StringStringIndexOfAfter);
diff --git a/compiler/optimizing/intrinsics_mips64.cc b/compiler/optimizing/intrinsics_mips64.cc
index e4627db..7b87b03 100644
--- a/compiler/optimizing/intrinsics_mips64.cc
+++ b/compiler/optimizing/intrinsics_mips64.cc
@@ -2358,7 +2358,6 @@
 UNIMPLEMENTED_INTRINSIC(MIPS64, CRC32UpdateBytes)
 UNIMPLEMENTED_INTRINSIC(MIPS64, CRC32UpdateByteBuffer)
 UNIMPLEMENTED_INTRINSIC(MIPS64, FP16ToFloat)
-UNIMPLEMENTED_INTRINSIC(MIPS64, FP16ToHalf)
 
 UNIMPLEMENTED_INTRINSIC(MIPS64, StringStringIndexOf);
 UNIMPLEMENTED_INTRINSIC(MIPS64, StringStringIndexOfAfter);
diff --git a/compiler/optimizing/intrinsics_x86.cc b/compiler/optimizing/intrinsics_x86.cc
index 95aa4c0..5a622ca 100644
--- a/compiler/optimizing/intrinsics_x86.cc
+++ b/compiler/optimizing/intrinsics_x86.cc
@@ -3082,7 +3082,6 @@
 UNIMPLEMENTED_INTRINSIC(X86, CRC32UpdateBytes)
 UNIMPLEMENTED_INTRINSIC(X86, CRC32UpdateByteBuffer)
 UNIMPLEMENTED_INTRINSIC(X86, FP16ToFloat)
-UNIMPLEMENTED_INTRINSIC(X86, FP16ToHalf)
 
 UNIMPLEMENTED_INTRINSIC(X86, StringStringIndexOf);
 UNIMPLEMENTED_INTRINSIC(X86, StringStringIndexOfAfter);
diff --git a/compiler/optimizing/intrinsics_x86_64.cc b/compiler/optimizing/intrinsics_x86_64.cc
index 8dbc0d3..cbf6606 100644
--- a/compiler/optimizing/intrinsics_x86_64.cc
+++ b/compiler/optimizing/intrinsics_x86_64.cc
@@ -2749,7 +2749,6 @@
 UNIMPLEMENTED_INTRINSIC(X86_64, CRC32UpdateBytes)
 UNIMPLEMENTED_INTRINSIC(X86_64, CRC32UpdateByteBuffer)
 UNIMPLEMENTED_INTRINSIC(X86_64, FP16ToFloat)
-UNIMPLEMENTED_INTRINSIC(X86_64, FP16ToHalf)
 
 UNIMPLEMENTED_INTRINSIC(X86_64, StringStringIndexOf);
 UNIMPLEMENTED_INTRINSIC(X86_64, StringStringIndexOfAfter);
diff --git a/runtime/hidden_api.h b/runtime/hidden_api.h
index 2ef3522..a21225b 100644
--- a/runtime/hidden_api.h
+++ b/runtime/hidden_api.h
@@ -358,7 +358,6 @@
         return 0u;
       case Intrinsics::kUnsafeGetLong:
       case Intrinsics::kFP16ToFloat:
-      case Intrinsics::kFP16ToHalf:
         return kAccCorePlatformApi;
       default:
         // Remaining intrinsics are public API. We DCHECK that in SetIntrinsic().
diff --git a/runtime/image.cc b/runtime/image.cc
index 256b957..11fac59 100644
--- a/runtime/image.cc
+++ b/runtime/image.cc
@@ -29,7 +29,7 @@
 namespace art {
 
 const uint8_t ImageHeader::kImageMagic[] = { 'a', 'r', 't', '\n' };
-const uint8_t ImageHeader::kImageVersion[] = { '0', '7', '9', '\0' };  // FP16ToHalf intrinsic
+const uint8_t ImageHeader::kImageVersion[] = { '0', '7', '8', '\0' };  // FP16ToFloat intrinsic
 
 ImageHeader::ImageHeader(uint32_t image_reservation_size,
                          uint32_t component_count,
diff --git a/runtime/interpreter/interpreter_intrinsics.cc b/runtime/interpreter/interpreter_intrinsics.cc
index 3759225..6b2d989 100644
--- a/runtime/interpreter/interpreter_intrinsics.cc
+++ b/runtime/interpreter/interpreter_intrinsics.cc
@@ -574,7 +574,6 @@
     UNIMPLEMENTED_CASE(CRC32UpdateBytes /* (I[BII)I */)
     UNIMPLEMENTED_CASE(CRC32UpdateByteBuffer /* (IJII)I */)
     UNIMPLEMENTED_CASE(FP16ToFloat /* (S)F */)
-    UNIMPLEMENTED_CASE(FP16ToHalf /* (F)S */)
     INTRINSIC_CASE(VarHandleFullFence)
     INTRINSIC_CASE(VarHandleAcquireFence)
     INTRINSIC_CASE(VarHandleReleaseFence)
diff --git a/runtime/intrinsics_list.h b/runtime/intrinsics_list.h
index bb41ca7..15ae309 100644
--- a/runtime/intrinsics_list.h
+++ b/runtime/intrinsics_list.h
@@ -166,7 +166,6 @@
   V(MemoryPokeLongNative, kStatic, kNeedsEnvironmentOrCache, kWriteSideEffects, kCanThrow, "Llibcore/io/Memory;", "pokeLongNative", "(JJ)V") \
   V(MemoryPokeShortNative, kStatic, kNeedsEnvironmentOrCache, kWriteSideEffects, kCanThrow, "Llibcore/io/Memory;", "pokeShortNative", "(JS)V") \
   V(FP16ToFloat, kStatic, kNeedsEnvironmentOrCache, kNoSideEffects, kNoThrow, "Llibcore/util/FP16;", "toFloat", "(S)F") \
-  V(FP16ToHalf, kStatic, kNeedsEnvironmentOrCache, kNoSideEffects, kNoThrow, "Llibcore/util/FP16;", "toHalf", "(F)S") \
   V(StringCharAt, kVirtual, kNeedsEnvironmentOrCache, kReadSideEffects, kCanThrow, "Ljava/lang/String;", "charAt", "(I)C") \
   V(StringCompareTo, kVirtual, kNeedsEnvironmentOrCache, kReadSideEffects, kCanThrow, "Ljava/lang/String;", "compareTo", "(Ljava/lang/String;)I") \
   V(StringEquals, kVirtual, kNeedsEnvironmentOrCache, kReadSideEffects, kCanThrow, "Ljava/lang/String;", "equals", "(Ljava/lang/Object;)Z") \
diff --git a/test/580-fp16/src-art/Main.java b/test/580-fp16/src-art/Main.java
index a89e100..798b52d 100644
--- a/test/580-fp16/src-art/Main.java
+++ b/test/580-fp16/src-art/Main.java
@@ -28,14 +28,15 @@
         return Float.floatToRawIntBits(f);
     }
 
-    public static void assertEquals(short expected, short calculated) {
-        if (expected != calculated) {
-            throw new Error("Expected: " + expected + ", Calculated: " + calculated);
+    public static void assertEquals(int expected, int actual) {
+        if (expected != actual) {
+            throw new Error("Expected: " + expected + ", found: " + actual);
         }
     }
-    public static void assertEquals(float expected, float calculated) {
-        if (expected != calculated) {
-            throw new Error("Expected: " + expected + ", Calculated: " + calculated);
+
+    public static void assertEquals(float expected, float actual) {
+        if (expected != actual) {
+            throw new Error("Expected: " + expected + ", found: " + actual);
         }
     }
 
@@ -46,48 +47,8 @@
                 // NaN inputs are tested below.
                 continue;
             }
-            assertEquals(h, FP16.toHalf(FP16.toFloat(h)));
+            assertEquals(FP16.toHalf(FP16.toFloat(h)), h);
         }
-
-        // These asserts check some known values and edge cases for FP16.toHalf
-        // and have been inspired by the cts HalfTest.
-        // Zeroes, NaN and infinities
-        assertEquals(FP16.POSITIVE_ZERO, FP16.toHalf(0.0f));
-        assertEquals(FP16.NEGATIVE_ZERO, FP16.toHalf(-0.0f));
-        assertEquals(FP16.NaN, FP16.toHalf(Float.NaN));
-        assertEquals(FP16.POSITIVE_INFINITY, FP16.toHalf(Float.POSITIVE_INFINITY));
-        assertEquals(FP16.NEGATIVE_INFINITY, FP16.toHalf(Float.NEGATIVE_INFINITY));
-        // Known values
-        assertEquals((short) 0x3c01, FP16.toHalf(1.0009765625f));
-        assertEquals((short) 0xc000, FP16.toHalf(-2.0f));
-        assertEquals((short) 0x0400, FP16.toHalf(6.10352e-5f));
-        assertEquals((short) 0x7bff, FP16.toHalf(65504.0f));
-        assertEquals((short) 0x3555, FP16.toHalf(1.0f / 3.0f));
-        // Subnormals
-        assertEquals((short) 0x03ff, FP16.toHalf(6.09756e-5f));
-        assertEquals(FP16.MIN_VALUE, FP16.toHalf(5.96046e-8f));
-        assertEquals((short) 0x83ff, FP16.toHalf(-6.09756e-5f));
-        assertEquals((short) 0x8001, FP16.toHalf(-5.96046e-8f));
-        // Subnormals (flushed to +/-0)
-        assertEquals(FP16.POSITIVE_ZERO, FP16.toHalf(5.96046e-9f));
-        assertEquals(FP16.NEGATIVE_ZERO, FP16.toHalf(-5.96046e-9f));
-        // Test for values that overflow the mantissa bits into exp bits
-        assertEquals(0x1000, FP16.toHalf(Float.intBitsToFloat(0x39fff000)));
-        assertEquals(0x0400, FP16.toHalf(Float.intBitsToFloat(0x387fe000)));
-        // Floats with absolute value above +/-65519 are rounded to +/-inf
-        // when using round-to-even
-        assertEquals(0x7bff, FP16.toHalf(65519.0f));
-        assertEquals(0x7bff, FP16.toHalf(65519.9f));
-        assertEquals(FP16.POSITIVE_INFINITY, FP16.toHalf(65520.0f));
-        assertEquals(FP16.NEGATIVE_INFINITY, FP16.toHalf(-65520.0f));
-        // Check if numbers are rounded to nearest even when they
-        // cannot be accurately represented by Half
-        assertEquals(0x6800, FP16.toHalf(2049.0f));
-        assertEquals(0x6c00, FP16.toHalf(4098.0f));
-        assertEquals(0x7000, FP16.toHalf(8196.0f));
-        assertEquals(0x7400, FP16.toHalf(16392.0f));
-        assertEquals(0x7800, FP16.toHalf(32784.0f));
-
         // FP16 SNaN/QNaN inputs to float
         // The most significant bit of mantissa:
         //                 V