| Message ID | 1340973784-30994-1-git-send-email-mans@mansr.com |
|---|---|
| State | Committed |
| Commit | 62634158b7cd39ad1e330a87153a97bf3dc6f8de |
| Headers | show |
On Fri, 29 Jun 2012, Mans Rullgard wrote: > This creates proper position independent code when accessing > data symbols if CONFIG_PIC is set. > > References to external symbols should now use the movrelx macro. > Some additional code changes are required since this macro may > need a register to hold the GOT pointer. > > Signed-off-by: Mans Rullgard <mans@mansr.com> > --- > This requires an updated gas-preprocessor for Apple builds. > Get it from https://github.com/mansr/gas-preprocessor > --- > libavcodec/arm/ac3dsp_armv6.S | 4 +-- > libavcodec/arm/fft_fixed_neon.S | 2 +- > libavcodec/arm/fft_neon.S | 4 +-- > libavcodec/arm/sbrdsp_neon.S | 4 +-- > libavcodec/arm/vp3dsp_neon.S | 3 +- > libavcodec/arm/vp8_armv6.S | 4 +-- > libavutil/arm/asm.S | 73 ++++++++++++++++++++++++++++++++++++++- > 7 files changed, 82 insertions(+), 12 deletions(-) Can't give much comments about the actual code, but I tested this on an ARMv6 iOS device, where it seemed to work. // Martin
On 2012-06-29 13:43:04 +0100, Måns Rullgård wrote: > This creates proper position independent code when accessing > data symbols if CONFIG_PIC is set. > > References to external symbols should now use the movrelx macro. > Some additional code changes are required since this macro may > need a register to hold the GOT pointer. > > Signed-off-by: Mans Rullgard <mans@mansr.com> > --- > This requires an updated gas-preprocessor for Apple builds. > Get it from https://github.com/mansr/gas-preprocessor > --- > libavcodec/arm/ac3dsp_armv6.S | 4 +-- > libavcodec/arm/fft_fixed_neon.S | 2 +- > libavcodec/arm/fft_neon.S | 4 +-- > libavcodec/arm/sbrdsp_neon.S | 4 +-- > libavcodec/arm/vp3dsp_neon.S | 3 +- > libavcodec/arm/vp8_armv6.S | 4 +-- > libavutil/arm/asm.S | 73 ++++++++++++++++++++++++++++++++++++++- > 7 files changed, 82 insertions(+), 12 deletions(-) > > diff --git a/libavcodec/arm/ac3dsp_armv6.S b/libavcodec/arm/ac3dsp_armv6.S > index 7e2f40e..f6f297a 100644 > --- a/libavcodec/arm/ac3dsp_armv6.S > +++ b/libavcodec/arm/ac3dsp_armv6.S > @@ -26,8 +26,8 @@ function ff_ac3_bit_alloc_calc_bap_armv6, export=1 > beq 4f > push {r4-r11,lr} > add r5, sp, #40 > - movrel r4, X(ff_ac3_bin_to_band_tab) > - movrel lr, X(ff_ac3_band_start_tab) > + movrelx r4, X(ff_ac3_bin_to_band_tab), r11 > + movrelx lr, X(ff_ac3_band_start_tab) > ldm r5, {r5-r7} > ldrb r4, [r4, r2] > add r1, r1, r2, lsl #1 @ psd + start > diff --git a/libavcodec/arm/fft_fixed_neon.S b/libavcodec/arm/fft_fixed_neon.S > index 4d891ba..faddc00 100644 > --- a/libavcodec/arm/fft_fixed_neon.S > +++ b/libavcodec/arm/fft_fixed_neon.S > @@ -214,7 +214,7 @@ function fft\n\()_neon > bl fft\n4\()_neon > mov r0, r4 > pop {r4, lr} > - movrel r1, X(ff_cos_\n\()_fixed) > + movrelx r1, X(ff_cos_\n\()_fixed) > mov r2, #\n4/2 > b fft_pass_neon > endfunc > diff --git a/libavcodec/arm/fft_neon.S b/libavcodec/arm/fft_neon.S > index aa06e6d..c4d8918 100644 > --- a/libavcodec/arm/fft_neon.S > +++ b/libavcodec/arm/fft_neon.S > @@ -143,7 +143,7 @@ function fft16_neon > vswp d29, d30 @ q14{r12,i12,i14,r15} q15{r13,i13,i15,r14} > vadd.f32 q0, q12, q13 @ {t1,t2,t5,t6} > vadd.f32 q1, q14, q15 @ {t1a,t2a,t5a,t6a} > - movrel r2, X(ff_cos_16) > + movrelx r2, X(ff_cos_16) > vsub.f32 q13, q12, q13 @ {t3,t4,t7,t8} > vrev64.32 d1, d1 > vsub.f32 q15, q14, q15 @ {t3a,t4a,t7a,t8a} > @@ -290,7 +290,7 @@ function fft\n\()_neon > bl fft\n4\()_neon > mov r0, r4 > pop {r4, lr} > - movrel r1, X(ff_cos_\n) > + movrelx r1, X(ff_cos_\n) > mov r2, #\n4/2 > b fft_pass_neon > endfunc > diff --git a/libavcodec/arm/sbrdsp_neon.S b/libavcodec/arm/sbrdsp_neon.S > index 4b681bf..610397f 100644 > --- a/libavcodec/arm/sbrdsp_neon.S > +++ b/libavcodec/arm/sbrdsp_neon.S > @@ -307,8 +307,8 @@ function ff_sbr_hf_apply_noise_0_neon, export=1 > vmov.i32 d3, #0 > .Lhf_apply_noise_0: > push {r4,lr} > + movrelx r4, X(ff_sbr_noise_table) > ldr r12, [sp, #12] > - movrel r4, X(ff_sbr_noise_table) > add r3, r3, #1 > bfc r3, #9, #23 > sub r12, r12, #1 > @@ -355,8 +355,8 @@ function ff_sbr_hf_apply_noise_1_neon, export=1 > eor lr, r12, #1<<31 > vmov d3, r12, lr > .Lhf_apply_noise_1: > + movrelx r4, X(ff_sbr_noise_table) > ldr r12, [sp, #12] > - movrel r4, X(ff_sbr_noise_table) > add r3, r3, #1 > bfc r3, #9, #23 > sub r12, r12, #1 > diff --git a/libavcodec/arm/vp3dsp_neon.S b/libavcodec/arm/vp3dsp_neon.S > index 8d22d00..2a9b25f 100644 > --- a/libavcodec/arm/vp3dsp_neon.S > +++ b/libavcodec/arm/vp3dsp_neon.S > @@ -116,9 +116,8 @@ function vp3_idct_start_neon > vadd.s16 q1, q8, q12 > vsub.s16 q8, q8, q12 > vld1.64 {d28-d31}, [r2,:128]! > -endfunc > > -function vp3_idct_core_neon > +vp3_idct_core_neon: > vmull.s16 q2, d18, xC1S7 // (ip[1] * C1) << 16 > vmull.s16 q3, d19, xC1S7 > vmull.s16 q4, d2, xC4S4 // ((ip[0] + ip[4]) * C4) << 16 not mentioned in the commit message, it looked unrelated before I saw the macro changes > diff --git a/libavcodec/arm/vp8_armv6.S b/libavcodec/arm/vp8_armv6.S > index 1fa6d15..1b668bc 100644 > --- a/libavcodec/arm/vp8_armv6.S > +++ b/libavcodec/arm/vp8_armv6.S > @@ -65,7 +65,7 @@ T orrcs \cw, \cw, \t1 > > function ff_decode_block_coeffs_armv6, export=1 > push {r0,r1,r4-r11,lr} > - movrel lr, X(ff_vp56_norm_shift) > + movrelx lr, X(ff_vp56_norm_shift) > ldrd r4, r5, [sp, #44] @ token_prob, qmul > cmp r3, #0 > ldr r11, [r5] > @@ -206,7 +206,7 @@ A orrcs r8, r8, r10, lsl r6 > mov r9, #8 > it ge > addge r12, r12, #1 > - movrel r4, X(ff_vp8_dct_cat_prob) > + movrelx r4, X(ff_vp8_dct_cat_prob), r1 > lsl r9, r9, r12 > ldr r4, [r4, r12, lsl #2] > add r12, r9, #3 > diff --git a/libavutil/arm/asm.S b/libavutil/arm/asm.S > index 6038a63..1508180 100644 > --- a/libavutil/arm/asm.S > +++ b/libavutil/arm/asm.S > @@ -62,7 +62,14 @@ ELF .eabi_attribute 25, \val > .endm > > .macro function name, export=0 > + .set .Lpic_idx, 0 > + .set .Lpic_gp, 0 > .macro endfunc > + .if .Lpic_idx > + .altmacro > + put_pic %(.Lpic_idx - 1) > + .noaltmacro > + .endif > ELF .size \name, . - \name > .endfunc > .purgem endfunc > @@ -106,8 +113,44 @@ ELF .size \name, . - \name > #endif > .endm > > +.macro put_pic num > + put_pic_\num > +.endm > + > +.macro do_def_pic num, val, label > + .macro put_pic_\num > + .if \num > + .altmacro > + put_pic %(\num - 1) > + .noaltmacro > + .endif > +\label: .word \val > + .purgem put_pic_\num > + .endm > +.endm > + > +.macro def_pic val, label > + .altmacro > + do_def_pic %.Lpic_idx, \val, \label > + .noaltmacro > + .set .Lpic_idx, .Lpic_idx + 1 > +.endm > + > +.macro ldpic rd, val, indir=0 > + ldr \rd, .Lpicoff\@ > +.Lpic\@: > + .if \indir > + ldr \rd, [pc, \rd] > + .else > + add \rd, pc, \rd > + .endif > + def_pic \val - (.Lpic\@ + (8 >> CONFIG_THUMB)), .Lpicoff\@ > +.endm > + > .macro movrel rd, val > -#if HAVE_ARMV6T2 && !CONFIG_PIC && !defined(__APPLE__) > +#if CONFIG_PIC > + ldpic \rd, \val > +#elif HAVE_ARMV6T2 && !defined(__APPLE__) > movw \rd, #:lower16:\val > movt \rd, #:upper16:\val > #else > @@ -115,6 +158,34 @@ ELF .size \name, . - \name > #endif > .endm > > +.macro movrelx rd, val, gp > +#if CONFIG_PIC && defined(__ELF__) > + .ifnb \gp > + .if .Lpic_gp > + .unreq gp > + .endif > + gp .req \gp > + ldpic gp, _GLOBAL_OFFSET_TABLE_ > + .elseif !.Lpic_gp > + gp .req r12 > + ldpic gp, _GLOBAL_OFFSET_TABLE_ > + .endif > + .set .Lpic_gp, 1 > + ldr \rd, .Lpicoff\@ > + ldr \rd, [gp, \rd] > + def_pic \val(GOT), .Lpicoff\@ > +#elif CONFIG_PIC && defined(__APPLE__) > + ldpic \rd, .Lpic\@, indir=1 > + .non_lazy_symbol_pointer > +.Lpic\@: > + .indirect_symbol \val > + .word 0 > + .text > +#else > + movrel \rd, \val > +#endif > +.endm > + > .macro ldr_pre rt, rn, rm:vararg > A ldr \rt, [\rn, \rm]! > T add \rn, \rn, \rm I would wish for something simpler. I can't see any obvious error and as it works as expected I guess it's ok. Janne
Janne Grunau <janne-libav@jannau.net> writes: >> diff --git a/libavcodec/arm/vp3dsp_neon.S b/libavcodec/arm/vp3dsp_neon.S >> index 8d22d00..2a9b25f 100644 >> --- a/libavcodec/arm/vp3dsp_neon.S >> +++ b/libavcodec/arm/vp3dsp_neon.S >> @@ -116,9 +116,8 @@ function vp3_idct_start_neon >> vadd.s16 q1, q8, q12 >> vsub.s16 q8, q8, q12 >> vld1.64 {d28-d31}, [r2,:128]! >> -endfunc >> >> -function vp3_idct_core_neon >> +vp3_idct_core_neon: >> vmull.s16 q2, d18, xC1S7 // (ip[1] * C1) << 16 >> vmull.s16 q3, d19, xC1S7 >> vmull.s16 q4, d2, xC4S4 // ((ip[0] + ip[4]) * C4) << 16 > > not mentioned in the commit message, it looked unrelated before I saw > the macro changes I guess I could have been clearer about that. [...] > I would wish for something simpler. If I could think of a simpler way, I'd use it. The problem is that gas only allows constants with the ldr reg, =val syntax, so I have to use macros to record the offsets as they are used and dump them at the end of the function.
diff --git a/libavcodec/arm/ac3dsp_armv6.S b/libavcodec/arm/ac3dsp_armv6.S index 7e2f40e..f6f297a 100644 --- a/libavcodec/arm/ac3dsp_armv6.S +++ b/libavcodec/arm/ac3dsp_armv6.S @@ -26,8 +26,8 @@ function ff_ac3_bit_alloc_calc_bap_armv6, export=1 beq 4f push {r4-r11,lr} add r5, sp, #40 - movrel r4, X(ff_ac3_bin_to_band_tab) - movrel lr, X(ff_ac3_band_start_tab) + movrelx r4, X(ff_ac3_bin_to_band_tab), r11 + movrelx lr, X(ff_ac3_band_start_tab) ldm r5, {r5-r7} ldrb r4, [r4, r2] add r1, r1, r2, lsl #1 @ psd + start diff --git a/libavcodec/arm/fft_fixed_neon.S b/libavcodec/arm/fft_fixed_neon.S index 4d891ba..faddc00 100644 --- a/libavcodec/arm/fft_fixed_neon.S +++ b/libavcodec/arm/fft_fixed_neon.S @@ -214,7 +214,7 @@ function fft\n\()_neon bl fft\n4\()_neon mov r0, r4 pop {r4, lr} - movrel r1, X(ff_cos_\n\()_fixed) + movrelx r1, X(ff_cos_\n\()_fixed) mov r2, #\n4/2 b fft_pass_neon endfunc diff --git a/libavcodec/arm/fft_neon.S b/libavcodec/arm/fft_neon.S index aa06e6d..c4d8918 100644 --- a/libavcodec/arm/fft_neon.S +++ b/libavcodec/arm/fft_neon.S @@ -143,7 +143,7 @@ function fft16_neon vswp d29, d30 @ q14{r12,i12,i14,r15} q15{r13,i13,i15,r14} vadd.f32 q0, q12, q13 @ {t1,t2,t5,t6} vadd.f32 q1, q14, q15 @ {t1a,t2a,t5a,t6a} - movrel r2, X(ff_cos_16) + movrelx r2, X(ff_cos_16) vsub.f32 q13, q12, q13 @ {t3,t4,t7,t8} vrev64.32 d1, d1 vsub.f32 q15, q14, q15 @ {t3a,t4a,t7a,t8a} @@ -290,7 +290,7 @@ function fft\n\()_neon bl fft\n4\()_neon mov r0, r4 pop {r4, lr} - movrel r1, X(ff_cos_\n) + movrelx r1, X(ff_cos_\n) mov r2, #\n4/2 b fft_pass_neon endfunc diff --git a/libavcodec/arm/sbrdsp_neon.S b/libavcodec/arm/sbrdsp_neon.S index 4b681bf..610397f 100644 --- a/libavcodec/arm/sbrdsp_neon.S +++ b/libavcodec/arm/sbrdsp_neon.S @@ -307,8 +307,8 @@ function ff_sbr_hf_apply_noise_0_neon, export=1 vmov.i32 d3, #0 .Lhf_apply_noise_0: push {r4,lr} + movrelx r4, X(ff_sbr_noise_table) ldr r12, [sp, #12] - movrel r4, X(ff_sbr_noise_table) add r3, r3, #1 bfc r3, #9, #23 sub r12, r12, #1 @@ -355,8 +355,8 @@ function ff_sbr_hf_apply_noise_1_neon, export=1 eor lr, r12, #1<<31 vmov d3, r12, lr .Lhf_apply_noise_1: + movrelx r4, X(ff_sbr_noise_table) ldr r12, [sp, #12] - movrel r4, X(ff_sbr_noise_table) add r3, r3, #1 bfc r3, #9, #23 sub r12, r12, #1 diff --git a/libavcodec/arm/vp3dsp_neon.S b/libavcodec/arm/vp3dsp_neon.S index 8d22d00..2a9b25f 100644 --- a/libavcodec/arm/vp3dsp_neon.S +++ b/libavcodec/arm/vp3dsp_neon.S @@ -116,9 +116,8 @@ function vp3_idct_start_neon vadd.s16 q1, q8, q12 vsub.s16 q8, q8, q12 vld1.64 {d28-d31}, [r2,:128]! -endfunc -function vp3_idct_core_neon +vp3_idct_core_neon: vmull.s16 q2, d18, xC1S7 // (ip[1] * C1) << 16 vmull.s16 q3, d19, xC1S7 vmull.s16 q4, d2, xC4S4 // ((ip[0] + ip[4]) * C4) << 16 diff --git a/libavcodec/arm/vp8_armv6.S b/libavcodec/arm/vp8_armv6.S index 1fa6d15..1b668bc 100644 --- a/libavcodec/arm/vp8_armv6.S +++ b/libavcodec/arm/vp8_armv6.S @@ -65,7 +65,7 @@ T orrcs \cw, \cw, \t1 function ff_decode_block_coeffs_armv6, export=1 push {r0,r1,r4-r11,lr} - movrel lr, X(ff_vp56_norm_shift) + movrelx lr, X(ff_vp56_norm_shift) ldrd r4, r5, [sp, #44] @ token_prob, qmul cmp r3, #0 ldr r11, [r5] @@ -206,7 +206,7 @@ A orrcs r8, r8, r10, lsl r6 mov r9, #8 it ge addge r12, r12, #1 - movrel r4, X(ff_vp8_dct_cat_prob) + movrelx r4, X(ff_vp8_dct_cat_prob), r1 lsl r9, r9, r12 ldr r4, [r4, r12, lsl #2] add r12, r9, #3 diff --git a/libavutil/arm/asm.S b/libavutil/arm/asm.S index 6038a63..1508180 100644 --- a/libavutil/arm/asm.S +++ b/libavutil/arm/asm.S @@ -62,7 +62,14 @@ ELF .eabi_attribute 25, \val .endm .macro function name, export=0 + .set .Lpic_idx, 0 + .set .Lpic_gp, 0 .macro endfunc + .if .Lpic_idx + .altmacro + put_pic %(.Lpic_idx - 1) + .noaltmacro + .endif ELF .size \name, . - \name .endfunc .purgem endfunc @@ -106,8 +113,44 @@ ELF .size \name, . - \name #endif .endm +.macro put_pic num + put_pic_\num +.endm + +.macro do_def_pic num, val, label + .macro put_pic_\num + .if \num + .altmacro + put_pic %(\num - 1) + .noaltmacro + .endif +\label: .word \val + .purgem put_pic_\num + .endm +.endm + +.macro def_pic val, label + .altmacro + do_def_pic %.Lpic_idx, \val, \label + .noaltmacro + .set .Lpic_idx, .Lpic_idx + 1 +.endm + +.macro ldpic rd, val, indir=0 + ldr \rd, .Lpicoff\@ +.Lpic\@: + .if \indir + ldr \rd, [pc, \rd] + .else + add \rd, pc, \rd + .endif + def_pic \val - (.Lpic\@ + (8 >> CONFIG_THUMB)), .Lpicoff\@ +.endm + .macro movrel rd, val -#if HAVE_ARMV6T2 && !CONFIG_PIC && !defined(__APPLE__) +#if CONFIG_PIC + ldpic \rd, \val +#elif HAVE_ARMV6T2 && !defined(__APPLE__) movw \rd, #:lower16:\val movt \rd, #:upper16:\val #else @@ -115,6 +158,34 @@ ELF .size \name, . - \name #endif .endm +.macro movrelx rd, val, gp +#if CONFIG_PIC && defined(__ELF__) + .ifnb \gp + .if .Lpic_gp + .unreq gp + .endif + gp .req \gp + ldpic gp, _GLOBAL_OFFSET_TABLE_ + .elseif !.Lpic_gp + gp .req r12 + ldpic gp, _GLOBAL_OFFSET_TABLE_ + .endif + .set .Lpic_gp, 1 + ldr \rd, .Lpicoff\@ + ldr \rd, [gp, \rd] + def_pic \val(GOT), .Lpicoff\@ +#elif CONFIG_PIC && defined(__APPLE__) + ldpic \rd, .Lpic\@, indir=1 + .non_lazy_symbol_pointer +.Lpic\@: + .indirect_symbol \val + .word 0 + .text +#else + movrel \rd, \val +#endif +.endm + .macro ldr_pre rt, rn, rm:vararg A ldr \rt, [\rn, \rm]! T add \rn, \rn, \rm
This creates proper position independent code when accessing data symbols if CONFIG_PIC is set. References to external symbols should now use the movrelx macro. Some additional code changes are required since this macro may need a register to hold the GOT pointer. Signed-off-by: Mans Rullgard <mans@mansr.com> --- This requires an updated gas-preprocessor for Apple builds. Get it from https://github.com/mansr/gas-preprocessor --- libavcodec/arm/ac3dsp_armv6.S | 4 +-- libavcodec/arm/fft_fixed_neon.S | 2 +- libavcodec/arm/fft_neon.S | 4 +-- libavcodec/arm/sbrdsp_neon.S | 4 +-- libavcodec/arm/vp3dsp_neon.S | 3 +- libavcodec/arm/vp8_armv6.S | 4 +-- libavutil/arm/asm.S | 73 ++++++++++++++++++++++++++++++++++++++- 7 files changed, 82 insertions(+), 12 deletions(-)