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| author | Maciej W. Rozycki <macro@codesourcery.com> | 2014-11-12 15:21:53 +0000 |
|---|---|---|
| committer | Leon Alrae <leon.alrae@imgtec.com> | 2014-12-16 12:45:20 +0000 |
| commit | 7215d7e7aea85699bf516c3e8d84f6a22584da35 (patch) | |
| tree | aff3ab7544db394ba03ee41a4eb54f671d59a3db /target-mips | |
| parent | 81a423e6c6d3ccaa79de4e58024369c660c1eeb4 (diff) | |
| download | qemu-7215d7e7aea85699bf516c3e8d84f6a22584da35.tar.gz | |
target-mips: Fix the 64-bit case for microMIPS MOVE16 and MOVEP
Fix microMIPS MOVE16 and MOVEP instructions on 64-bit processors by
using register addition operations.
This copies the approach taken with MIPS16 MOVE instructions (I8_MOV32R
and I8_MOVR32 opcodes) and follows the observation that OPC_ADDU expands
to tcg_gen_mov_tl whenever `rt' is 0 and `rs' is not, therefore copying
`rs' to `rd' verbatim. This is not the case with OPC_ADDIU where a
sign-extension from bit #31 is made, unless in the uninteresting case of
`rs' being 0, losing the upper 32 bits of the value copied for any
proper 64-bit values.
This also serves as an optimization as one op is produced in generated
code rather than two (again, unless `rs' is 0, where it doesn't change
anything).
Signed-off-by: Maciej W. Rozycki <macro@codesourcery.com>
Reviewed-by: Leon Alrae <leon.alrae@imgtec.com>
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
Diffstat (limited to 'target-mips')
| -rw-r--r-- | target-mips/translate.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/target-mips/translate.c b/target-mips/translate.c index b5d5b39092..1a275bf099 100644 --- a/target-mips/translate.c +++ b/target-mips/translate.c @@ -13936,8 +13936,8 @@ static int decode_micromips_opc (CPUMIPSState *env, DisasContext *ctx) rs = rs_rt_enc[enc_rs]; rt = rs_rt_enc[enc_rt]; - gen_arith_imm(ctx, OPC_ADDIU, rd, rs, 0); - gen_arith_imm(ctx, OPC_ADDIU, re, rt, 0); + gen_arith(ctx, OPC_ADDU, rd, rs, 0); + gen_arith(ctx, OPC_ADDU, re, rt, 0); } break; case LBU16: @@ -14018,7 +14018,7 @@ static int decode_micromips_opc (CPUMIPSState *env, DisasContext *ctx) int rd = uMIPS_RD5(ctx->opcode); int rs = uMIPS_RS5(ctx->opcode); - gen_arith_imm(ctx, OPC_ADDIU, rd, rs, 0); + gen_arith(ctx, OPC_ADDU, rd, rs, 0); } break; case ANDI16: |