commit 675e09b2753c2fcd521bd8f0230a0abf06e9b0e9
author Ningsheng Jian <ningsheng.jian@arm.com> Thu Oct 23 13:48:36 2014 +0800
committer Ian Rogers <irogers@google.com> Wed Nov 05 11:37:37 2014 -0800
tree 9a5f41cb1dd1930ae003feeccb4211d59b465e19
parent 211d45e059935a7874a1ec89846f03d35ffba29f

ARM: Strength reduction for floating-point division

For floating-point division by power of two constants, generate
multiplication by the reciprocal instead.

Change-Id: I39c79eeb26b60cc754ad42045362b79498c755be

compiler/dex/quick/mir_to_lir.cc

diff --git a/compiler/dex/quick/mir_to_lir.cc b/compiler/dex/quick/mir_to_lir.cc
index 533a677..ccaa167 100644
--- a/compiler/dex/quick/mir_to_lir.cc
+++ b/compiler/dex/quick/mir_to_lir.cc
@@ -1052,28 +1052,36 @@
       }
       break;
 
+    case Instruction::DIV_FLOAT:
+    case Instruction::DIV_FLOAT_2ADDR:
+      if (HandleEasyFloatingPointDiv(rl_dest, rl_src[0], rl_src[1])) {
+        break;
+      }
+      FALLTHROUGH_INTENDED;
     case Instruction::ADD_FLOAT:
     case Instruction::SUB_FLOAT:
     case Instruction::MUL_FLOAT:
-    case Instruction::DIV_FLOAT:
     case Instruction::REM_FLOAT:
     case Instruction::ADD_FLOAT_2ADDR:
     case Instruction::SUB_FLOAT_2ADDR:
     case Instruction::MUL_FLOAT_2ADDR:
-    case Instruction::DIV_FLOAT_2ADDR:
     case Instruction::REM_FLOAT_2ADDR:
       GenArithOpFloat(opcode, rl_dest, rl_src[0], rl_src[1]);
       break;
 
+    case Instruction::DIV_DOUBLE:
+    case Instruction::DIV_DOUBLE_2ADDR:
+      if (HandleEasyFloatingPointDiv(rl_dest, rl_src[0], rl_src[1])) {
+        break;
+      }
+      FALLTHROUGH_INTENDED;
     case Instruction::ADD_DOUBLE:
     case Instruction::SUB_DOUBLE:
     case Instruction::MUL_DOUBLE:
-    case Instruction::DIV_DOUBLE:
     case Instruction::REM_DOUBLE:
     case Instruction::ADD_DOUBLE_2ADDR:
     case Instruction::SUB_DOUBLE_2ADDR:
     case Instruction::MUL_DOUBLE_2ADDR:
-    case Instruction::DIV_DOUBLE_2ADDR:
     case Instruction::REM_DOUBLE_2ADDR:
       GenArithOpDouble(opcode, rl_dest, rl_src[0], rl_src[1]);
       break;