OK applying to arm/embedded-4_9-branch, though you still need maintainer approval into trunk.
- Joey On Wed, Nov 26, 2014 at 11:43 AM, Hale Wang <hale.w...@arm.com> wrote: > Hi, > > This patch ports the aeabi_idiv routine from Linaro Cortex-Strings > (https://git.linaro.org/toolchain/cortex-strings.git), which was contributed > by ARM under Free BSD license. > > The new aeabi_idiv routine is used to replace the one in > libgcc/config/arm/lib1funcs.S. This replacement happens within the Thumb1 > wrapper. The new routine is under LGPLv3 license. > > The main advantage of this version is that it can improve the performance of > the aeabi_idiv function for Thumb1. This solution will also increase the > code size. So it will only be used if __OPTIMIZE_SIZE__ is not defined. > > Make check passed for armv6-m. > > OK for trunk? > > Thanks, > Hale Wang > > libgcc/ChangeLog: > > 2014-11-26 Hale Wang <hale.w...@arm.com> > > * config/arm/lib1funcs.S: Add new wrapper. > > =============================================== > diff --git a/libgcc/config/arm/lib1funcs.S b/libgcc/config/arm/lib1funcs.S > index b617137..de66c81 100644 > --- a/libgcc/config/arm/lib1funcs.S > +++ b/libgcc/config/arm/lib1funcs.S > @@ -306,34 +306,12 @@ LSYM(Lend_fde): > #ifdef __ARM_EABI__ > .macro THUMB_LDIV0 name signed > #if defined(__ARM_ARCH_6M__) > - .ifc \signed, unsigned > - cmp r0, #0 > - beq 1f > - mov r0, #0 > - mvn r0, r0 @ 0xffffffff > -1: > - .else > - cmp r0, #0 > - beq 2f > - blt 3f > + > + push {r0, lr} > mov r0, #0 > - mvn r0, r0 > - lsr r0, r0, #1 @ 0x7fffffff > - b 2f > -3: mov r0, #0x80 > - lsl r0, r0, #24 @ 0x80000000 > -2: > - .endif > - push {r0, r1, r2} > - ldr r0, 4f > - adr r1, 4f > - add r0, r1 > - str r0, [sp, #8] > - @ We know we are not on armv4t, so pop pc is safe. > - pop {r0, r1, pc} > - .align 2 > -4: > - .word __aeabi_idiv0 - 4b > + bl SYM(__aeabi_idiv0) > + pop {r1, pc} > + > #elif defined(__thumb2__) > .syntax unified > .ifc \signed, unsigned > @@ -927,7 +905,158 @@ LSYM(Lover7): > add dividend, work > .endif > LSYM(Lgot_result): > -.endm > +.endm > + > +#if defined(__prefer_thumb__) && !defined(__OPTIMIZE_SIZE__) > +.macro BranchToDiv n, label > + lsr curbit, dividend, \n > + cmp curbit, divisor > + blo \label > +.endm > + > +.macro DoDiv n > + lsr curbit, dividend, \n > + cmp curbit, divisor > + bcc 1f > + lsl curbit, divisor, \n > + sub dividend, dividend, curbit > + > +1: adc result, result > +.endm > + > +.macro THUMB1_Div_Positive > + mov result, #0 > + BranchToDiv #1, LSYM(Lthumb1_div1) > + BranchToDiv #4, LSYM(Lthumb1_div4) > + BranchToDiv #8, LSYM(Lthumb1_div8) > + BranchToDiv #12, LSYM(Lthumb1_div12) > + BranchToDiv #16, LSYM(Lthumb1_div16) > +LSYM(Lthumb1_div_large_positive): > + mov result, #0xff > + lsl divisor, divisor, #8 > + rev result, result > + lsr curbit, dividend, #16 > + cmp curbit, divisor > + blo 1f > + asr result, #8 > + lsl divisor, divisor, #8 > + beq LSYM(Ldivbyzero_waypoint) > + > +1: lsr curbit, dividend, #12 > + cmp curbit, divisor > + blo LSYM(Lthumb1_div12) > + b LSYM(Lthumb1_div16) > +LSYM(Lthumb1_div_loop): > + lsr divisor, divisor, #8 > +LSYM(Lthumb1_div16): > + Dodiv #15 > + Dodiv #14 > + Dodiv #13 > + Dodiv #12 > +LSYM(Lthumb1_div12): > + Dodiv #11 > + Dodiv #10 > + Dodiv #9 > + Dodiv #8 > + bcs LSYM(Lthumb1_div_loop) > +LSYM(Lthumb1_div8): > + Dodiv #7 > + Dodiv #6 > + Dodiv #5 > +LSYM(Lthumb1_div5): > + Dodiv #4 > +LSYM(Lthumb1_div4): > + Dodiv #3 > +LSYM(Lthumb1_div3): > + Dodiv #2 > +LSYM(Lthumb1_div2): > + Dodiv #1 > +LSYM(Lthumb1_div1): > + sub divisor, dividend, divisor > + bcs 1f > + cpy divisor, dividend > + > +1: adc result, result > + cpy dividend, result > + RET > + > +LSYM(Ldivbyzero_waypoint): > + b LSYM(Ldiv0) > +.endm > + > +.macro THUMB1_Div_Negative > + lsr result, divisor, #31 > + beq 1f > + neg divisor, divisor > + > +1: asr curbit, dividend, #32 > + bcc 2f > + neg dividend, dividend > + > +2: eor curbit, result > + mov result, #0 > + cpy ip, curbit > + BranchToDiv #4, LSYM(Lthumb1_div_negative4) > + BranchToDiv #8, LSYM(Lthumb1_div_negative8) > +LSYM(Lthumb1_div_large): > + mov result, #0xfc > + lsl divisor, divisor, #6 > + rev result, result > + lsr curbit, dividend, #8 > + cmp curbit, divisor > + blo LSYM(Lthumb1_div_negative8) > + > + lsl divisor, divisor, #6 > + asr result, result, #6 > + cmp curbit, divisor > + blo LSYM(Lthumb1_div_negative8) > + > + lsl divisor, divisor, #6 > + asr result, result, #6 > + cmp curbit, divisor > + blo LSYM(Lthumb1_div_negative8) > + > + lsl divisor, divisor, #6 > + beq LSYM(Ldivbyzero_negative) > + asr result, result, #6 > + b LSYM(Lthumb1_div_negative8) > +LSYM(Lthumb1_div_negative_loop): > + lsr divisor, divisor, #6 > +LSYM(Lthumb1_div_negative8): > + DoDiv #7 > + DoDiv #6 > + DoDiv #5 > + DoDiv #4 > +LSYM(Lthumb1_div_negative4): > + DoDiv #3 > + DoDiv #2 > + bcs LSYM(Lthumb1_div_negative_loop) > + DoDiv #1 > + sub divisor, dividend, divisor > + bcs 1f > + cpy divisor, dividend > + > +1: cpy curbit, ip > + adc result, result > + asr curbit, curbit, #1 > + cpy dividend, result > + bcc 2f > + neg dividend, dividend > + cmp curbit, #0 > + > +2: bpl 3f > + neg divisor, divisor > + > +3: RET > + > +LSYM(Ldivbyzero_negative): > + cpy curbit, ip > + asr curbit, curbit, #1 > + bcc LSYM(Ldiv0) > + neg dividend, dividend > +.endm > +#endif /* ARM Thumb version. */ > + > /* ------------------------------------------------------------------------ > */ > /* Start of the Real Functions > */ > /* ------------------------------------------------------------------------ > */ > @@ -937,6 +1066,7 @@ LSYM(Lgot_result): > > FUNC_START udivsi3 > FUNC_ALIAS aeabi_uidiv udivsi3 > +#if defined(__OPTIMIZE_SIZE__) > > cmp divisor, #0 > beq LSYM(Ldiv0) > @@ -954,6 +1084,13 @@ LSYM(udivsi3_skip_div0_test): > pop { work } > RET > > +#else > + > +LSYM(udivsi3_skip_div0_test): > + THUMB1_Div_Positive > + > +#endif > + > #elif defined(__ARM_ARCH_EXT_IDIV__) > > ARM_FUNC_START udivsi3 > @@ -1066,7 +1203,7 @@ LSYM(Lover10): > RET > > #else /* ARM version. */ > - > + > FUNC_START umodsi3 > > subs r2, r1, #1 @ compare divisor with 1 > @@ -1091,8 +1228,9 @@ LSYM(Lover10): > > #if defined(__prefer_thumb__) > > - FUNC_START divsi3 > + FUNC_START divsi3 > FUNC_ALIAS aeabi_idiv divsi3 > +#if defined(__OPTIMIZE_SIZE__) > > cmp divisor, #0 > beq LSYM(Ldiv0) > @@ -1115,7 +1253,7 @@ LSYM(Lover11): > blo LSYM(Lgot_result) > > THUMB_DIV_MOD_BODY 0 > - > + > mov r0, result > mov work, ip > cmp work, #0 > @@ -1124,6 +1262,20 @@ LSYM(Lover11): > LSYM(Lover12): > pop { work } > RET > +#else > + > +LSYM(divsi3_skip_div0_test): > + cpy curbit, dividend > + orr curbit, divisor > + bmi LSYM(Lthumb1_div_negative) > + > +LSYM(Lthumb1_div_positive): > + THUMB1_Div_Positive > + > +LSYM(Lthumb1_div_negative): > + THUMB1_Div_Negative > + > +#endif /* __OPTIMIZE_SIZE__ */ > > #elif defined(__ARM_ARCH_EXT_IDIV__) > > @@ -1136,8 +1288,8 @@ LSYM(Lover12): > RET > > #else /* ARM/Thumb-2 version. */ > - > - ARM_FUNC_START divsi3 > + > + ARM_FUNC_START divsi3 > ARM_FUNC_ALIAS aeabi_idiv divsi3 > > cmp r1, #0 > ===============================================
