| Andreas Gampe | 4b537a8 | 2014-06-30 22:24:53 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2014 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | #ifndef ART_COMPILER_DEX_REG_LOCATION_H_ |
| 18 | #define ART_COMPILER_DEX_REG_LOCATION_H_ |
| 19 | |
| 20 | #include "reg_storage.h" |
| 21 | |
| 22 | namespace art { |
| 23 | |
| 24 | |
| 25 | /* |
| 26 | * Whereas a SSA name describes a definition of a Dalvik vreg, the RegLocation describes |
| 27 | * the type of an SSA name (and, can also be used by code generators to record where the |
| 28 | * value is located (i.e. - physical register, frame, spill, etc.). For each SSA name (SReg) |
| 29 | * there is a RegLocation. |
| 30 | * A note on SSA names: |
| 31 | * o SSA names for Dalvik vRegs v0..vN will be assigned 0..N. These represent the "vN_0" |
| 32 | * names. Negative SSA names represent special values not present in the Dalvik byte code. |
| 33 | * For example, SSA name -1 represents an invalid SSA name, and SSA name -2 represents the |
| 34 | * the Method pointer. SSA names < -2 are reserved for future use. |
| 35 | * o The vN_0 names for non-argument Dalvik should in practice never be used (as they would |
| 36 | * represent the read of an undefined local variable). The first definition of the |
| 37 | * underlying Dalvik vReg will result in a vN_1 name. |
| 38 | * |
| 39 | * FIXME: The orig_sreg field was added as a workaround for llvm bitcode generation. With |
| 40 | * the latest restructuring, we should be able to remove it and rely on s_reg_low throughout. |
| 41 | */ |
| 42 | struct RegLocation { |
| 43 | RegLocationType location:3; |
| 44 | unsigned wide:1; |
| 45 | unsigned defined:1; // Do we know the type? |
| 46 | unsigned is_const:1; // Constant, value in mir_graph->constant_values[]. |
| 47 | unsigned fp:1; // Floating point? |
| 48 | unsigned core:1; // Non-floating point? |
| 49 | unsigned ref:1; // Something GC cares about. |
| 50 | unsigned high_word:1; // High word of pair? |
| 51 | unsigned home:1; // Does this represent the home location? |
| 52 | RegStorage reg; // Encoded physical registers. |
| 53 | int16_t s_reg_low; // SSA name for low Dalvik word. |
| 54 | int16_t orig_sreg; // TODO: remove after Bitcode gen complete |
| 55 | // and consolidate usage w/ s_reg_low. |
| 56 | }; |
| 57 | |
| 58 | } // namespace art |
| 59 | |
| 60 | #endif // ART_COMPILER_DEX_REG_LOCATION_H_ |