openkylin
/
qemu
mirror of https://gitee.com/openkylin/qemu.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

Do constant folding for shift operations. 

Perform constant forlding for SHR, SHL, SAR, ROTR, ROTL operations.

Signed-off-by: Kirill Batuzov <batuzovk@ispras.ru>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
This commit is contained in:
Kirill Batuzov 2011-07-07 16:37:16 +04:00 committed by Blue Swirl
parent 9a81090b12
commit 55c0975c5b
1 changed files with 72 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

72
tcg/optimize.c
View File

@ -102,6 +102,11 @@ static int op_bits(int op)
case INDEX_op_and_i32:
case INDEX_op_or_i32:
case INDEX_op_xor_i32:
case INDEX_op_shl_i32:
case INDEX_op_shr_i32:
case INDEX_op_sar_i32:
case INDEX_op_rotl_i32:
case INDEX_op_rotr_i32:
return 32;
#if TCG_TARGET_REG_BITS == 64
case INDEX_op_mov_i64:
@ -111,6 +116,11 @@ static int op_bits(int op)
case INDEX_op_and_i64:
case INDEX_op_or_i64:
case INDEX_op_xor_i64:
case INDEX_op_shl_i64:
case INDEX_op_shr_i64:
case INDEX_op_sar_i64:
case INDEX_op_rotl_i64:
case INDEX_op_rotr_i64:
return 64;
#endif
default:
@ -205,6 +215,58 @@ static TCGArg do_constant_folding_2(int op, TCGArg x, TCGArg y)
CASE_OP_32_64(xor):
return x ^ y;
case INDEX_op_shl_i32:
return (uint32_t)x << (uint32_t)y;
#if TCG_TARGET_REG_BITS == 64
case INDEX_op_shl_i64:
return (uint64_t)x << (uint64_t)y;
#endif
case INDEX_op_shr_i32:
return (uint32_t)x >> (uint32_t)y;
#if TCG_TARGET_REG_BITS == 64
case INDEX_op_shr_i64:
return (uint64_t)x >> (uint64_t)y;
#endif
case INDEX_op_sar_i32:
return (int32_t)x >> (int32_t)y;
#if TCG_TARGET_REG_BITS == 64
case INDEX_op_sar_i64:
return (int64_t)x >> (int64_t)y;
#endif
case INDEX_op_rotr_i32:
#if TCG_TARGET_REG_BITS == 64
x &= 0xffffffff;
y &= 0xffffffff;
#endif
x = (x << (32 - y)) | (x >> y);
return x;
#if TCG_TARGET_REG_BITS == 64
case INDEX_op_rotr_i64:
x = (x << (64 - y)) | (x >> y);
return x;
#endif
case INDEX_op_rotl_i32:
#if TCG_TARGET_REG_BITS == 64
x &= 0xffffffff;
y &= 0xffffffff;
#endif
x = (x << y) | (x >> (32 - y));
return x;
#if TCG_TARGET_REG_BITS == 64
case INDEX_op_rotl_i64:
x = (x << y) | (x >> (64 - y));
return x;
#endif
default:
fprintf(stderr,
"Unrecognized operation %d in do_constant_folding.\n", op);
@ -278,6 +340,11 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
switch (op) {
CASE_OP_32_64(add):
CASE_OP_32_64(sub):
CASE_OP_32_64(shl):
CASE_OP_32_64(shr):
CASE_OP_32_64(sar):
CASE_OP_32_64(rotl):
CASE_OP_32_64(rotr):
if (temps[args[1]].state == TCG_TEMP_CONST) {
/* Proceed with possible constant folding. */
break;
@ -363,6 +430,11 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
CASE_OP_32_64(or):
CASE_OP_32_64(and):
CASE_OP_32_64(xor):
CASE_OP_32_64(shl):
CASE_OP_32_64(shr):
CASE_OP_32_64(sar):
CASE_OP_32_64(rotl):
CASE_OP_32_64(rotr):
if (temps[args[1]].state == TCG_TEMP_CONST
&& temps[args[2]].state == TCG_TEMP_CONST) {
gen_opc_buf[op_index] = op_to_movi(op);