commit 3e6a3bf797e49b7f449256455c7e522e888687d8
author Mark Mendell <mark.p.mendell@intel.com> Mon Jan 19 14:09:22 2015 -0500
committer Mark P Mendell <mark.p.mendell@intel.com> Fri Jan 30 13:17:23 2015 +0000
tree 1e574169ff7743729cdfb1b9cf3b217f198a330d
parent 9544368685b4aa65e746332e602491a3e8e5b247

ART: Change x86 long param ABI (Quick/JNI/Opt)

Ensure that we don't pass a long parameter across the last register
and the stack: skip the register and allocate it only on the stack.
This was requested to simplify the optimizing compiler code
generation for x86.

Optimizing (Baseline) compiler support for x86 longs:
- Remove QuickParameter from Location, as there are no longer any uses
  of it.

Bump oat.h version because we changed an ABI again.

I changed IsParamALong() to return false for argument 0 (this argument).
I am not sure why it differed from all other tests.

I have not tested on ARM.  I followed Nicolas's suggestions for setting
the value of kSplitPairAcrossRegisterAndStack for different
architectures.

Change-Id: I2f16b33c1dac58dd4f4f503e9c2309d845f5fb7a
Signed-off-by: Mark Mendell <mark.p.mendell@intel.com>

runtime/entrypoints/quick/quick_trampoline_entrypoints.cc

diff --git a/runtime/entrypoints/quick/quick_trampoline_entrypoints.cc b/runtime/entrypoints/quick/quick_trampoline_entrypoints.cc
index a67ebca..98f1684 100644
--- a/runtime/entrypoints/quick/quick_trampoline_entrypoints.cc
+++ b/runtime/entrypoints/quick/quick_trampoline_entrypoints.cc
@@ -59,6 +59,7 @@
   // | S0         |
   // |            |    4x2 bytes padding
   // | Method*    |  <- sp
+  static constexpr bool kSplitPairAcrossRegisterAndStack = kArm32QuickCodeUseSoftFloat;
   static constexpr bool kAlignPairRegister = !kArm32QuickCodeUseSoftFloat;
   static constexpr bool kQuickSoftFloatAbi = kArm32QuickCodeUseSoftFloat;
   static constexpr bool kQuickDoubleRegAlignedFloatBackFilled = !kArm32QuickCodeUseSoftFloat;
@@ -95,6 +96,7 @@
   // | D0         |
   // |            |    padding
   // | Method*    |  <- sp
+  static constexpr bool kSplitPairAcrossRegisterAndStack = false;
   static constexpr bool kAlignPairRegister = false;
   static constexpr bool kQuickSoftFloatAbi = false;  // This is a hard float ABI.
   static constexpr bool kQuickDoubleRegAlignedFloatBackFilled = false;
@@ -125,6 +127,7 @@
   // | A2         |    arg2
   // | A1         |    arg1
   // | A0/Method* |  <- sp
+  static constexpr bool kSplitPairAcrossRegisterAndStack = true;
   static constexpr bool kAlignPairRegister = false;
   static constexpr bool kQuickSoftFloatAbi = true;  // This is a soft float ABI.
   static constexpr bool kQuickDoubleRegAlignedFloatBackFilled = false;
@@ -203,6 +206,7 @@
   // | XMM1        |    float arg 2
   // | XMM0        |    float arg 1
   // | EAX/Method* |  <- sp
+  static constexpr bool kSplitPairAcrossRegisterAndStack = false;
   static constexpr bool kAlignPairRegister = false;
   static constexpr bool kQuickSoftFloatAbi = false;  // This is a hard float ABI.
   static constexpr bool kQuickDoubleRegAlignedFloatBackFilled = false;
@@ -243,6 +247,7 @@
   // | XMM0            |    float arg 1
   // | Padding         |
   // | RDI/Method*     |  <- sp
+  static constexpr bool kSplitPairAcrossRegisterAndStack = false;
   static constexpr bool kAlignPairRegister = false;
   static constexpr bool kQuickSoftFloatAbi = false;  // This is a hard float ABI.
   static constexpr bool kQuickDoubleRegAlignedFloatBackFilled = false;
@@ -452,6 +457,11 @@
             }
             is_split_long_or_double_ = (GetBytesPerGprSpillLocation(kRuntimeISA) == 4) &&
                 ((gpr_index_ + 1) == kNumQuickGprArgs);
+            if (!kSplitPairAcrossRegisterAndStack && is_split_long_or_double_) {
+              // We don't want to split this. Pass over this register.
+              gpr_index_++;
+              is_split_long_or_double_ = false;
+            }
             Visit();
             if (kBytesStackArgLocation == 4) {
               stack_index_+= 2;