From: Ralf Baechle Date: Wed, 30 Apr 2014 09:21:55 +0000 (+0200) Subject: MIPS: math-emu: Switch to using the MIPS rounding modes. X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=56a6473339dbd2e908cf8c6f2856d5de2bf8d15b;p=openwrt%2Fstaging%2Fblogic.git MIPS: math-emu: Switch to using the MIPS rounding modes. Previously math-emu was using the IEEE-754 constants internally. These were differing by having the constants for rounding to +/- infinity switched, so a conversion was necessary. This would be entirely avoidable if the MIPS constants were used throughout, so get rid of the bloat. Signed-off-by: Ralf Baechle --- diff --git a/arch/mips/math-emu/cp1emu.c b/arch/mips/math-emu/cp1emu.c index b31ce6cdb6b9..03e233223af7 100644 --- a/arch/mips/math-emu/cp1emu.c +++ b/arch/mips/math-emu/cp1emu.c @@ -67,21 +67,6 @@ static int fpux_emu(struct pt_regs *, /* Determine rounding mode from the RM bits of the FCSR */ #define modeindex(v) ((v) & FPU_CSR_RM) -/* Convert MIPS rounding mode (0..3) to IEEE library modes. */ -static const unsigned char ieee_rm[4] = { - [FPU_CSR_RN] = IEEE754_RN, - [FPU_CSR_RZ] = IEEE754_RZ, - [FPU_CSR_RU] = IEEE754_RU, - [FPU_CSR_RD] = IEEE754_RD, -}; -/* Convert IEEE library modes to MIPS rounding mode (0..3). */ -static const unsigned char mips_rm[4] = { - [IEEE754_RN] = FPU_CSR_RN, - [IEEE754_RZ] = FPU_CSR_RZ, - [IEEE754_RD] = FPU_CSR_RD, - [IEEE754_RU] = FPU_CSR_RU, -}; - /* convert condition code register number to csr bit */ static const unsigned int fpucondbit[8] = { FPU_CSR_COND0, @@ -907,8 +892,7 @@ emul: /* cop control register rd -> gpr[rt] */ if (MIPSInst_RD(ir) == FPCREG_CSR) { value = ctx->fcr31; - value = (value & ~FPU_CSR_RM) | - mips_rm[modeindex(value)]; + value = (value & ~FPU_CSR_RM) | modeindex(value); pr_debug("%p gpr[%d]<-csr=%08x\n", (void *) (xcp->cp0_epc), MIPSInst_RT(ir), value); @@ -939,9 +923,8 @@ emul: * Don't write reserved bits, * and convert to ieee library modes */ - ctx->fcr31 = (value & - ~(FPU_CSR_RSVD | FPU_CSR_RM)) | - ieee_rm[modeindex(value)]; + ctx->fcr31 = (value & ~(FPU_CSR_RSVD | FPU_CSR_RM)) | + modeindex(value); } if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) { return SIGFPE; @@ -1515,7 +1498,7 @@ copcsr: oldrm = ieee754_csr.rm; SPFROMREG(fs, MIPSInst_FS(ir)); - ieee754_csr.rm = ieee_rm[modeindex(MIPSInst_FUNC(ir))]; + ieee754_csr.rm = modeindex(MIPSInst_FUNC(ir)); rv.w = ieee754sp_tint(fs); ieee754_csr.rm = oldrm; rfmt = w_fmt; @@ -1539,7 +1522,7 @@ copcsr: oldrm = ieee754_csr.rm; SPFROMREG(fs, MIPSInst_FS(ir)); - ieee754_csr.rm = ieee_rm[modeindex(MIPSInst_FUNC(ir))]; + ieee754_csr.rm = modeindex(MIPSInst_FUNC(ir)); rv.l = ieee754sp_tlong(fs); ieee754_csr.rm = oldrm; rfmt = l_fmt; @@ -1692,7 +1675,7 @@ dcopuop: oldrm = ieee754_csr.rm; DPFROMREG(fs, MIPSInst_FS(ir)); - ieee754_csr.rm = ieee_rm[modeindex(MIPSInst_FUNC(ir))]; + ieee754_csr.rm = modeindex(MIPSInst_FUNC(ir)); rv.w = ieee754dp_tint(fs); ieee754_csr.rm = oldrm; rfmt = w_fmt; @@ -1716,7 +1699,7 @@ dcopuop: oldrm = ieee754_csr.rm; DPFROMREG(fs, MIPSInst_FS(ir)); - ieee754_csr.rm = ieee_rm[modeindex(MIPSInst_FUNC(ir))]; + ieee754_csr.rm = modeindex(MIPSInst_FUNC(ir)); rv.l = ieee754dp_tlong(fs); ieee754_csr.rm = oldrm; rfmt = l_fmt; @@ -1926,11 +1909,7 @@ int fpu_emulator_cop1Handler(struct pt_regs *xcp, struct mips_fpu_struct *ctx, * ieee754_csr. But ieee754_csr.rm is ieee * library modes. (not mips rounding mode) */ - /* convert to ieee library modes */ - ieee754_csr.rm = ieee_rm[ieee754_csr.rm]; sig = cop1Emulate(xcp, ctx, dec_insn, fault_addr); - /* revert to mips rounding mode */ - ieee754_csr.rm = mips_rm[ieee754_csr.rm]; } if (has_fpu) diff --git a/arch/mips/math-emu/dp_add.c b/arch/mips/math-emu/dp_add.c index 9c98b96f7287..7f64577df984 100644 --- a/arch/mips/math-emu/dp_add.c +++ b/arch/mips/math-emu/dp_add.c @@ -91,7 +91,7 @@ union ieee754dp ieee754dp_add(union ieee754dp x, union ieee754dp y) if (xs == ys) return x; else - return ieee754dp_zero(ieee754_csr.rm == IEEE754_RD); + return ieee754dp_zero(ieee754_csr.rm == FPU_CSR_RD); case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO): case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO): @@ -168,7 +168,7 @@ union ieee754dp ieee754dp_add(union ieee754dp x, union ieee754dp y) xs = ys; } if (xm == 0) - return ieee754dp_zero(ieee754_csr.rm == IEEE754_RD); + return ieee754dp_zero(ieee754_csr.rm == FPU_CSR_RD); /* * Normalize to rounding precision. diff --git a/arch/mips/math-emu/dp_sqrt.c b/arch/mips/math-emu/dp_sqrt.c index 0384c094b1aa..041bbb6124bb 100644 --- a/arch/mips/math-emu/dp_sqrt.c +++ b/arch/mips/math-emu/dp_sqrt.c @@ -80,7 +80,7 @@ union ieee754dp ieee754dp_sqrt(union ieee754dp x) oldcsr = ieee754_csr; ieee754_csr.mx &= ~IEEE754_INEXACT; ieee754_csr.sx &= ~IEEE754_INEXACT; - ieee754_csr.rm = IEEE754_RN; + ieee754_csr.rm = FPU_CSR_RN; /* adjust exponent to prevent overflow */ scalx = 0; @@ -122,7 +122,7 @@ union ieee754dp ieee754dp_sqrt(union ieee754dp x) /* twiddle last bit to force y correctly rounded */ /* set RZ, clear INEX flag */ - ieee754_csr.rm = IEEE754_RZ; + ieee754_csr.rm = FPU_CSR_RZ; ieee754_csr.sx &= ~IEEE754_INEXACT; /* t=x/y; ...chopped quotient, possibly inexact */ @@ -139,10 +139,10 @@ union ieee754dp ieee754dp_sqrt(union ieee754dp x) oldcsr.sx |= IEEE754_INEXACT; switch (oldcsr.rm) { - case IEEE754_RU: + case FPU_CSR_RU: y.bits += 1; /* drop through */ - case IEEE754_RN: + case FPU_CSR_RN: t.bits += 1; break; } diff --git a/arch/mips/math-emu/dp_sub.c b/arch/mips/math-emu/dp_sub.c index d502984df7cc..7a174029043a 100644 --- a/arch/mips/math-emu/dp_sub.c +++ b/arch/mips/math-emu/dp_sub.c @@ -91,7 +91,7 @@ union ieee754dp ieee754dp_sub(union ieee754dp x, union ieee754dp y) if (xs != ys) return x; else - return ieee754dp_zero(ieee754_csr.rm == IEEE754_RD); + return ieee754dp_zero(ieee754_csr.rm == FPU_CSR_RD); case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO): case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO): @@ -171,7 +171,7 @@ union ieee754dp ieee754dp_sub(union ieee754dp x, union ieee754dp y) xs = ys; } if (xm == 0) { - if (ieee754_csr.rm == IEEE754_RD) + if (ieee754_csr.rm == FPU_CSR_RD) return ieee754dp_zero(1); /* round negative inf. => sign = -1 */ else return ieee754dp_zero(0); /* other round modes => sign = 1 */ diff --git a/arch/mips/math-emu/dp_tint.c b/arch/mips/math-emu/dp_tint.c index 972dba0baca0..6ffc336c530e 100644 --- a/arch/mips/math-emu/dp_tint.c +++ b/arch/mips/math-emu/dp_tint.c @@ -74,17 +74,17 @@ int ieee754dp_tint(union ieee754dp x) to be zero */ odd = (xm & 0x1) != 0x0; switch (ieee754_csr.rm) { - case IEEE754_RN: + case FPU_CSR_RN: if (round && (sticky || odd)) xm++; break; - case IEEE754_RZ: + case FPU_CSR_RZ: break; - case IEEE754_RU: /* toward +Infinity */ + case FPU_CSR_RU: /* toward +Infinity */ if ((round || sticky) && !xs) xm++; break; - case IEEE754_RD: /* toward -Infinity */ + case FPU_CSR_RD: /* toward -Infinity */ if ((round || sticky) && xs) xm++; break; diff --git a/arch/mips/math-emu/dp_tlong.c b/arch/mips/math-emu/dp_tlong.c index afaf953e576d..9cdc145b75e0 100644 --- a/arch/mips/math-emu/dp_tlong.c +++ b/arch/mips/math-emu/dp_tlong.c @@ -79,17 +79,17 @@ s64 ieee754dp_tlong(union ieee754dp x) } odd = (xm & 0x1) != 0x0; switch (ieee754_csr.rm) { - case IEEE754_RN: + case FPU_CSR_RN: if (round && (sticky || odd)) xm++; break; - case IEEE754_RZ: + case FPU_CSR_RZ: break; - case IEEE754_RU: /* toward +Infinity */ + case FPU_CSR_RU: /* toward +Infinity */ if ((round || sticky) && !xs) xm++; break; - case IEEE754_RD: /* toward -Infinity */ + case FPU_CSR_RD: /* toward -Infinity */ if ((round || sticky) && xs) xm++; break; diff --git a/arch/mips/math-emu/ieee754.h b/arch/mips/math-emu/ieee754.h index 2fa939c612f6..43c4fb522ac2 100644 --- a/arch/mips/math-emu/ieee754.h +++ b/arch/mips/math-emu/ieee754.h @@ -126,13 +126,6 @@ enum { #define IEEE754_CGT 0x04 #define IEEE754_CUN 0x08 -/* rounding mode -*/ -#define IEEE754_RN 0 /* round to nearest */ -#define IEEE754_RZ 1 /* round toward zero */ -#define IEEE754_RD 2 /* round toward -Infinity */ -#define IEEE754_RU 3 /* round toward +Infinity */ - /* "normal" comparisons */ static inline int ieee754sp_eq(union ieee754sp x, union ieee754sp y) diff --git a/arch/mips/math-emu/ieee754dp.c b/arch/mips/math-emu/ieee754dp.c index 087a6f38b149..fd134675fc2e 100644 --- a/arch/mips/math-emu/ieee754dp.c +++ b/arch/mips/math-emu/ieee754dp.c @@ -67,17 +67,17 @@ static u64 ieee754dp_get_rounding(int sn, u64 xm) */ if (xm & (DP_MBIT(3) - 1)) { switch (ieee754_csr.rm) { - case IEEE754_RZ: + case FPU_CSR_RZ: break; - case IEEE754_RN: + case FPU_CSR_RN: xm += 0x3 + ((xm >> 3) & 1); /* xm += (xm&0x8)?0x4:0x3 */ break; - case IEEE754_RU: /* toward +Infinity */ + case FPU_CSR_RU: /* toward +Infinity */ if (!sn) /* ?? */ xm += 0x8; break; - case IEEE754_RD: /* toward -Infinity */ + case FPU_CSR_RD: /* toward -Infinity */ if (sn) /* ?? */ xm += 0x8; break; @@ -108,15 +108,15 @@ union ieee754dp ieee754dp_format(int sn, int xe, u64 xm) ieee754_setcx(IEEE754_INEXACT); switch(ieee754_csr.rm) { - case IEEE754_RN: - case IEEE754_RZ: + case FPU_CSR_RN: + case FPU_CSR_RZ: return ieee754dp_zero(sn); - case IEEE754_RU: /* toward +Infinity */ + case FPU_CSR_RU: /* toward +Infinity */ if (sn == 0) return ieee754dp_min(0); else return ieee754dp_zero(1); - case IEEE754_RD: /* toward -Infinity */ + case FPU_CSR_RD: /* toward -Infinity */ if (sn == 0) return ieee754dp_zero(0); else @@ -172,16 +172,16 @@ union ieee754dp ieee754dp_format(int sn, int xe, u64 xm) ieee754_setcx(IEEE754_INEXACT); /* -O can be table indexed by (rm,sn) */ switch (ieee754_csr.rm) { - case IEEE754_RN: + case FPU_CSR_RN: return ieee754dp_inf(sn); - case IEEE754_RZ: + case FPU_CSR_RZ: return ieee754dp_max(sn); - case IEEE754_RU: /* toward +Infinity */ + case FPU_CSR_RU: /* toward +Infinity */ if (sn == 0) return ieee754dp_inf(0); else return ieee754dp_max(1); - case IEEE754_RD: /* toward -Infinity */ + case FPU_CSR_RD: /* toward -Infinity */ if (sn == 0) return ieee754dp_max(0); else diff --git a/arch/mips/math-emu/ieee754sp.c b/arch/mips/math-emu/ieee754sp.c index e4cec15845b9..d348efe91445 100644 --- a/arch/mips/math-emu/ieee754sp.c +++ b/arch/mips/math-emu/ieee754sp.c @@ -67,17 +67,17 @@ static unsigned ieee754sp_get_rounding(int sn, unsigned xm) */ if (xm & (SP_MBIT(3) - 1)) { switch (ieee754_csr.rm) { - case IEEE754_RZ: + case FPU_CSR_RZ: break; - case IEEE754_RN: + case FPU_CSR_RN: xm += 0x3 + ((xm >> 3) & 1); /* xm += (xm&0x8)?0x4:0x3 */ break; - case IEEE754_RU: /* toward +Infinity */ + case FPU_CSR_RU: /* toward +Infinity */ if (!sn) /* ?? */ xm += 0x8; break; - case IEEE754_RD: /* toward -Infinity */ + case FPU_CSR_RD: /* toward -Infinity */ if (sn) /* ?? */ xm += 0x8; break; @@ -108,15 +108,15 @@ union ieee754sp ieee754sp_format(int sn, int xe, unsigned xm) ieee754_setcx(IEEE754_INEXACT); switch(ieee754_csr.rm) { - case IEEE754_RN: - case IEEE754_RZ: + case FPU_CSR_RN: + case FPU_CSR_RZ: return ieee754sp_zero(sn); - case IEEE754_RU: /* toward +Infinity */ + case FPU_CSR_RU: /* toward +Infinity */ if (sn == 0) return ieee754sp_min(0); else return ieee754sp_zero(1); - case IEEE754_RD: /* toward -Infinity */ + case FPU_CSR_RD: /* toward -Infinity */ if (sn == 0) return ieee754sp_zero(0); else @@ -170,16 +170,16 @@ union ieee754sp ieee754sp_format(int sn, int xe, unsigned xm) ieee754_setcx(IEEE754_INEXACT); /* -O can be table indexed by (rm,sn) */ switch (ieee754_csr.rm) { - case IEEE754_RN: + case FPU_CSR_RN: return ieee754sp_inf(sn); - case IEEE754_RZ: + case FPU_CSR_RZ: return ieee754sp_max(sn); - case IEEE754_RU: /* toward +Infinity */ + case FPU_CSR_RU: /* toward +Infinity */ if (sn == 0) return ieee754sp_inf(0); else return ieee754sp_max(1); - case IEEE754_RD: /* toward -Infinity */ + case FPU_CSR_RD: /* toward -Infinity */ if (sn == 0) return ieee754sp_max(0); else diff --git a/arch/mips/math-emu/sp_add.c b/arch/mips/math-emu/sp_add.c index a0bc95cea1cc..2d84d460cb67 100644 --- a/arch/mips/math-emu/sp_add.c +++ b/arch/mips/math-emu/sp_add.c @@ -91,7 +91,7 @@ union ieee754sp ieee754sp_add(union ieee754sp x, union ieee754sp y) if (xs == ys) return x; else - return ieee754sp_zero(ieee754_csr.rm == IEEE754_RD); + return ieee754sp_zero(ieee754_csr.rm == FPU_CSR_RD); case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO): case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO): @@ -165,7 +165,7 @@ union ieee754sp ieee754sp_add(union ieee754sp x, union ieee754sp y) xs = ys; } if (xm == 0) - return ieee754sp_zero(ieee754_csr.rm == IEEE754_RD); + return ieee754sp_zero(ieee754_csr.rm == FPU_CSR_RD); /* * Normalize in extended single precision diff --git a/arch/mips/math-emu/sp_fdp.c b/arch/mips/math-emu/sp_fdp.c index 90b9ec45e984..1b266fb16973 100644 --- a/arch/mips/math-emu/sp_fdp.c +++ b/arch/mips/math-emu/sp_fdp.c @@ -57,8 +57,8 @@ union ieee754sp ieee754sp_fdp(union ieee754dp x) /* can't possibly be sp representable */ ieee754_setcx(IEEE754_UNDERFLOW); ieee754_setcx(IEEE754_INEXACT); - if ((ieee754_csr.rm == IEEE754_RU && !xs) || - (ieee754_csr.rm == IEEE754_RD && xs)) + if ((ieee754_csr.rm == FPU_CSR_RU && !xs) || + (ieee754_csr.rm == FPU_CSR_RD && xs)) return ieee754sp_mind(xs); return ieee754sp_zero(xs); diff --git a/arch/mips/math-emu/sp_sqrt.c b/arch/mips/math-emu/sp_sqrt.c index 94f5befa1d70..b7c098a86f95 100644 --- a/arch/mips/math-emu/sp_sqrt.c +++ b/arch/mips/math-emu/sp_sqrt.c @@ -100,10 +100,10 @@ union ieee754sp ieee754sp_sqrt(union ieee754sp x) if (ix != 0) { ieee754_setcx(IEEE754_INEXACT); switch (ieee754_csr.rm) { - case IEEE754_RU: + case FPU_CSR_RU: q += 2; break; - case IEEE754_RN: + case FPU_CSR_RN: q += (q & 1); break; } diff --git a/arch/mips/math-emu/sp_sub.c b/arch/mips/math-emu/sp_sub.c index e813f4fee784..8592e49032b8 100644 --- a/arch/mips/math-emu/sp_sub.c +++ b/arch/mips/math-emu/sp_sub.c @@ -91,7 +91,7 @@ union ieee754sp ieee754sp_sub(union ieee754sp x, union ieee754sp y) if (xs != ys) return x; else - return ieee754sp_zero(ieee754_csr.rm == IEEE754_RD); + return ieee754sp_zero(ieee754_csr.rm == FPU_CSR_RD); case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO): case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO): @@ -165,7 +165,7 @@ union ieee754sp ieee754sp_sub(union ieee754sp x, union ieee754sp y) xs = ys; } if (xm == 0) { - if (ieee754_csr.rm == IEEE754_RD) + if (ieee754_csr.rm == FPU_CSR_RD) return ieee754sp_zero(1); /* round negative inf. => sign = -1 */ else return ieee754sp_zero(0); /* other round modes => sign = 1 */ diff --git a/arch/mips/math-emu/sp_tint.c b/arch/mips/math-emu/sp_tint.c index e1dee56ebc54..091299a31798 100644 --- a/arch/mips/math-emu/sp_tint.c +++ b/arch/mips/math-emu/sp_tint.c @@ -79,17 +79,17 @@ int ieee754sp_tint(union ieee754sp x) } odd = (xm & 0x1) != 0x0; switch (ieee754_csr.rm) { - case IEEE754_RN: + case FPU_CSR_RN: if (round && (sticky || odd)) xm++; break; - case IEEE754_RZ: + case FPU_CSR_RZ: break; - case IEEE754_RU: /* toward +Infinity */ + case FPU_CSR_RU: /* toward +Infinity */ if ((round || sticky) && !xs) xm++; break; - case IEEE754_RD: /* toward -Infinity */ + case FPU_CSR_RD: /* toward -Infinity */ if ((round || sticky) && xs) xm++; break; diff --git a/arch/mips/math-emu/sp_tlong.c b/arch/mips/math-emu/sp_tlong.c index 67eff6ba9e18..9f3c742c1cea 100644 --- a/arch/mips/math-emu/sp_tlong.c +++ b/arch/mips/math-emu/sp_tlong.c @@ -76,17 +76,17 @@ s64 ieee754sp_tlong(union ieee754sp x) } odd = (xm & 0x1) != 0x0; switch (ieee754_csr.rm) { - case IEEE754_RN: + case FPU_CSR_RN: if (round && (sticky || odd)) xm++; break; - case IEEE754_RZ: + case FPU_CSR_RZ: break; - case IEEE754_RU: /* toward +Infinity */ + case FPU_CSR_RU: /* toward +Infinity */ if ((round || sticky) && !xs) xm++; break; - case IEEE754_RD: /* toward -Infinity */ + case FPU_CSR_RD: /* toward -Infinity */ if ((round || sticky) && xs) xm++; break;