* [Qemu-devel] [PATCH v3] target-arm: Add support for AArch32 64bit VCVTB and VCVTT
@ 2014-01-29 10:31 Will Newton
2014-02-04 19:21 ` Peter Maydell
0 siblings, 1 reply; 2+ messages in thread
From: Will Newton @ 2014-01-29 10:31 UTC (permalink / raw)
To: qemu-devel; +Cc: Peter Maydell, patches
Add support for the AArch32 floating-point half-precision to double-
precision conversion VCVTB and VCVTT instructions.
Signed-off-by: Will Newton <will.newton@linaro.org>
---
target-arm/translate.c | 74 ++++++++++++++++++++++++++++++++++++++------------
1 file changed, 56 insertions(+), 18 deletions(-)
Changes in v3:
- Fix comments as per review
- Tidy up single precision source logic
diff --git a/target-arm/translate.c b/target-arm/translate.c
index e701c0f..9ca357c 100644
--- a/target-arm/translate.c
+++ b/target-arm/translate.c
@@ -3142,16 +3142,19 @@ static int disas_vfp_insn(CPUARMState * env, DisasContext *s, uint32_t insn)
VFP_DREG_N(rn, insn);
}
- if (op == 15 && (rn == 15 || ((rn & 0x1c) == 0x18))) {
- /* Integer or single precision destination. */
+ if (op == 15 && (rn == 15 || ((rn & 0x1c) == 0x18) ||
+ ((rn & 0x1e) == 0x6))) {
+ /* Integer or single/half precision destination. */
rd = VFP_SREG_D(insn);
} else {
VFP_DREG_D(rd, insn);
}
if (op == 15 &&
- (((rn & 0x1c) == 0x10) || ((rn & 0x14) == 0x14))) {
- /* VCVT from int is always from S reg regardless of dp bit.
- * VCVT with immediate frac_bits has same format as SREG_M
+ (((rn & 0x1c) == 0x10) || ((rn & 0x14) == 0x14) ||
+ ((rn & 0x1e) == 0x4))) {
+ /* VCVT from int or half precision is always from S reg
+ * regardless of dp bit. VCVT with immediate frac_bits
+ * has same format as SREG_M.
*/
rm = VFP_SREG_M(insn);
} else {
@@ -3241,12 +3244,19 @@ static int disas_vfp_insn(CPUARMState * env, DisasContext *s, uint32_t insn)
case 5:
case 6:
case 7:
- /* VCVTB, VCVTT: only present with the halfprec extension,
- * UNPREDICTABLE if bit 8 is set (we choose to UNDEF)
+ /* VCVTB, VCVTT: only present with the halfprec extension
+ * UNPREDICTABLE if bit 8 is set prior to ARMv8
+ * (we choose to UNDEF)
*/
- if (dp || !arm_feature(env, ARM_FEATURE_VFP_FP16)) {
+ if ((dp && !arm_feature(env, ARM_FEATURE_V8)) ||
+ !arm_feature(env, ARM_FEATURE_VFP_FP16)) {
return 1;
}
+ if (!extract32(rn, 1, 1)) {
+ /* Half precision source. */
+ gen_mov_F0_vreg(0, rm);
+ break;
+ }
/* Otherwise fall through */
default:
/* One source operand. */
@@ -3394,21 +3404,39 @@ static int disas_vfp_insn(CPUARMState * env, DisasContext *s, uint32_t insn)
case 3: /* sqrt */
gen_vfp_sqrt(dp);
break;
- case 4: /* vcvtb.f32.f16 */
+ case 4: /* vcvtb.f32.f16, vcvtb.f64.f16 */
tmp = gen_vfp_mrs();
tcg_gen_ext16u_i32(tmp, tmp);
- gen_helper_vfp_fcvt_f16_to_f32(cpu_F0s, tmp, cpu_env);
+ if (dp) {
+ gen_helper_vfp_fcvt_f16_to_f64(cpu_F0d, tmp,
+ cpu_env);
+ } else {
+ gen_helper_vfp_fcvt_f16_to_f32(cpu_F0s, tmp,
+ cpu_env);
+ }
tcg_temp_free_i32(tmp);
break;
- case 5: /* vcvtt.f32.f16 */
+ case 5: /* vcvtt.f32.f16, vcvtt.f64.f16 */
tmp = gen_vfp_mrs();
tcg_gen_shri_i32(tmp, tmp, 16);
- gen_helper_vfp_fcvt_f16_to_f32(cpu_F0s, tmp, cpu_env);
+ if (dp) {
+ gen_helper_vfp_fcvt_f16_to_f64(cpu_F0d, tmp,
+ cpu_env);
+ } else {
+ gen_helper_vfp_fcvt_f16_to_f32(cpu_F0s, tmp,
+ cpu_env);
+ }
tcg_temp_free_i32(tmp);
break;
- case 6: /* vcvtb.f16.f32 */
+ case 6: /* vcvtb.f16.f32, vcvtb.f16.f64 */
tmp = tcg_temp_new_i32();
- gen_helper_vfp_fcvt_f32_to_f16(tmp, cpu_F0s, cpu_env);
+ if (dp) {
+ gen_helper_vfp_fcvt_f64_to_f16(tmp, cpu_F0d,
+ cpu_env);
+ } else {
+ gen_helper_vfp_fcvt_f32_to_f16(tmp, cpu_F0s,
+ cpu_env);
+ }
gen_mov_F0_vreg(0, rd);
tmp2 = gen_vfp_mrs();
tcg_gen_andi_i32(tmp2, tmp2, 0xffff0000);
@@ -3416,9 +3444,15 @@ static int disas_vfp_insn(CPUARMState * env, DisasContext *s, uint32_t insn)
tcg_temp_free_i32(tmp2);
gen_vfp_msr(tmp);
break;
- case 7: /* vcvtt.f16.f32 */
+ case 7: /* vcvtt.f16.f32, vcvtt.f16.f64 */
tmp = tcg_temp_new_i32();
- gen_helper_vfp_fcvt_f32_to_f16(tmp, cpu_F0s, cpu_env);
+ if (dp) {
+ gen_helper_vfp_fcvt_f64_to_f16(tmp, cpu_F0d,
+ cpu_env);
+ } else {
+ gen_helper_vfp_fcvt_f32_to_f16(tmp, cpu_F0s,
+ cpu_env);
+ }
tcg_gen_shli_i32(tmp, tmp, 16);
gen_mov_F0_vreg(0, rd);
tmp2 = gen_vfp_mrs();
@@ -3553,8 +3587,12 @@ static int disas_vfp_insn(CPUARMState * env, DisasContext *s, uint32_t insn)
/* Write back the result. */
if (op == 15 && (rn >= 8 && rn <= 11))
; /* Comparison, do nothing. */
- else if (op == 15 && dp && ((rn & 0x1c) == 0x18))
- /* VCVT double to int: always integer result. */
+ else if (op == 15 && dp && ((rn & 0x1c) == 0x18 ||
+ (rn & 0x1e) == 0x6))
+ /* VCVT double to int: always integer result.
+ * VCVT double to half precision is always a single
+ * precision result.
+ */
gen_mov_vreg_F0(0, rd);
else if (op == 15 && rn == 15)
/* conversion */
--
1.8.1.4
^ permalink raw reply related [flat|nested] 2+ messages in thread
* Re: [Qemu-devel] [PATCH v3] target-arm: Add support for AArch32 64bit VCVTB and VCVTT
2014-01-29 10:31 [Qemu-devel] [PATCH v3] target-arm: Add support for AArch32 64bit VCVTB and VCVTT Will Newton
@ 2014-02-04 19:21 ` Peter Maydell
0 siblings, 0 replies; 2+ messages in thread
From: Peter Maydell @ 2014-02-04 19:21 UTC (permalink / raw)
To: Will Newton; +Cc: QEMU Developers, Patch Tracking
On 29 January 2014 10:31, Will Newton <will.newton@linaro.org> wrote:
> Add support for the AArch32 floating-point half-precision to double-
> precision conversion VCVTB and VCVTT instructions.
>
> Signed-off-by: Will Newton <will.newton@linaro.org>
Thanks; I've fixed a minor style issue (missing braces on
an if-ladder your patch touches) and applied this to
target-arm.next.
-- PMM
^ permalink raw reply [flat|nested] 2+ messages in thread
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