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From: David Gibson <david@gibson.dropbear.id.au>
To: "Paul A. Clarke" <pc@us.ibm.com>
Cc: richard.henderson@linaro.org, qemu-ppc@nongnu.org, qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] [PATCH] ppc: Use FPSCR defines instead of constants
Date: Thu, 19 Sep 2019 16:30:00 +1000	[thread overview]
Message-ID: <20190919063000.GE22790@umbus.fritz.box> (raw)
In-Reply-To: <1568817169-1721-1-git-send-email-pc@us.ibm.com>

[-- Attachment #1: Type: text/plain, Size: 18775 bytes --]

On Wed, Sep 18, 2019 at 09:32:49AM -0500, Paul A. Clarke wrote:
> From: "Paul A. Clarke" <pc@us.ibm.com>
> 
> There are FPSCR-related defines in target/ppc/cpu.h which can be used in
> place of constants and explicit shifts which arguably improve the code a
> bit in places.
> 
> Signed-off-by: Paul A. Clarke <pc@us.ibm.com>

Applied to ppc-for-4.2, thanks.

> ---
> I confirmed that the generated assembly is identical before and after
> the patch.
> 
>  target/ppc/dfp_helper.c |   8 ++--
>  target/ppc/fpu_helper.c | 122 ++++++++++++++++++++++++------------------------
>  2 files changed, 65 insertions(+), 65 deletions(-)
> 
> diff --git a/target/ppc/dfp_helper.c b/target/ppc/dfp_helper.c
> index da8e08a..7533991 100644
> --- a/target/ppc/dfp_helper.c
> +++ b/target/ppc/dfp_helper.c
> @@ -220,8 +220,8 @@ static void dfp_set_FPRF_from_FRT_with_context(struct PPC_DFP *dfp,
>      default:
>          assert(0); /* should never get here */
>      }
> -    dfp->env->fpscr &= ~(0x1F << 12);
> -    dfp->env->fpscr |= (fprf << 12);
> +    dfp->env->fpscr &= ~FP_FPRF;
> +    dfp->env->fpscr |= (fprf << FPSCR_FPRF);
>  }
>  
>  static void dfp_set_FPRF_from_FRT(struct PPC_DFP *dfp)
> @@ -369,8 +369,8 @@ static void dfp_set_CRBF_from_T(struct PPC_DFP *dfp)
>  
>  static void dfp_set_FPCC_from_CRBF(struct PPC_DFP *dfp)
>  {
> -    dfp->env->fpscr &= ~(0xF << 12);
> -    dfp->env->fpscr |= (dfp->crbf << 12);
> +    dfp->env->fpscr &= ~FP_FPCC;
> +    dfp->env->fpscr |= (dfp->crbf << FPSCR_FPCC);
>  }
>  
>  static inline void dfp_makeQNaN(decNumber *dn)
> diff --git a/target/ppc/fpu_helper.c b/target/ppc/fpu_helper.c
> index 4b1a2e6..dc38324 100644
> --- a/target/ppc/fpu_helper.c
> +++ b/target/ppc/fpu_helper.c
> @@ -180,7 +180,7 @@ static void set_fprf_from_class(CPUPPCState *env, int class)
>      };
>      bool isneg = class & is_neg;
>  
> -    env->fpscr &= ~(0x1F << FPSCR_FPRF);
> +    env->fpscr &= ~FP_FPRF;
>      env->fpscr |= fprf[ctz32(class)][isneg] << FPSCR_FPRF;
>  }
>  
> @@ -199,12 +199,12 @@ COMPUTE_FPRF(float128)
>  static void finish_invalid_op_excp(CPUPPCState *env, int op, uintptr_t retaddr)
>  {
>      /* Update the floating-point invalid operation summary */
> -    env->fpscr |= 1 << FPSCR_VX;
> +    env->fpscr |= FP_VX;
>      /* Update the floating-point exception summary */
>      env->fpscr |= FP_FX;
>      if (fpscr_ve != 0) {
>          /* Update the floating-point enabled exception summary */
> -        env->fpscr |= 1 << FPSCR_FEX;
> +        env->fpscr |= FP_FEX;
>          if (fp_exceptions_enabled(env)) {
>              raise_exception_err_ra(env, POWERPC_EXCP_PROGRAM,
>                                     POWERPC_EXCP_FP | op, retaddr);
> @@ -215,11 +215,11 @@ static void finish_invalid_op_excp(CPUPPCState *env, int op, uintptr_t retaddr)
>  static void finish_invalid_op_arith(CPUPPCState *env, int op,
>                                      bool set_fpcc, uintptr_t retaddr)
>  {
> -    env->fpscr &= ~((1 << FPSCR_FR) | (1 << FPSCR_FI));
> +    env->fpscr &= ~(FP_FR | FP_FI);
>      if (fpscr_ve == 0) {
>          if (set_fpcc) {
> -            env->fpscr &= ~(0xF << FPSCR_FPCC);
> -            env->fpscr |= 0x11 << FPSCR_FPCC;
> +            env->fpscr &= ~FP_FPCC;
> +            env->fpscr |= (FP_C | FP_FU);
>          }
>      }
>      finish_invalid_op_excp(env, op, retaddr);
> @@ -228,7 +228,7 @@ static void finish_invalid_op_arith(CPUPPCState *env, int op,
>  /* Signalling NaN */
>  static void float_invalid_op_vxsnan(CPUPPCState *env, uintptr_t retaddr)
>  {
> -    env->fpscr |= 1 << FPSCR_VXSNAN;
> +    env->fpscr |= FP_VXSNAN;
>      finish_invalid_op_excp(env, POWERPC_EXCP_FP_VXSNAN, retaddr);
>  }
>  
> @@ -236,7 +236,7 @@ static void float_invalid_op_vxsnan(CPUPPCState *env, uintptr_t retaddr)
>  static void float_invalid_op_vxisi(CPUPPCState *env, bool set_fpcc,
>                                     uintptr_t retaddr)
>  {
> -    env->fpscr |= 1 << FPSCR_VXISI;
> +    env->fpscr |= FP_VXISI;
>      finish_invalid_op_arith(env, POWERPC_EXCP_FP_VXISI, set_fpcc, retaddr);
>  }
>  
> @@ -244,7 +244,7 @@ static void float_invalid_op_vxisi(CPUPPCState *env, bool set_fpcc,
>  static void float_invalid_op_vxidi(CPUPPCState *env, bool set_fpcc,
>                                     uintptr_t retaddr)
>  {
> -    env->fpscr |= 1 << FPSCR_VXIDI;
> +    env->fpscr |= FP_VXIDI;
>      finish_invalid_op_arith(env, POWERPC_EXCP_FP_VXIDI, set_fpcc, retaddr);
>  }
>  
> @@ -252,7 +252,7 @@ static void float_invalid_op_vxidi(CPUPPCState *env, bool set_fpcc,
>  static void float_invalid_op_vxzdz(CPUPPCState *env, bool set_fpcc,
>                                     uintptr_t retaddr)
>  {
> -    env->fpscr |= 1 << FPSCR_VXZDZ;
> +    env->fpscr |= FP_VXZDZ;
>      finish_invalid_op_arith(env, POWERPC_EXCP_FP_VXZDZ, set_fpcc, retaddr);
>  }
>  
> @@ -260,7 +260,7 @@ static void float_invalid_op_vxzdz(CPUPPCState *env, bool set_fpcc,
>  static void float_invalid_op_vximz(CPUPPCState *env, bool set_fpcc,
>                                     uintptr_t retaddr)
>  {
> -    env->fpscr |= 1 << FPSCR_VXIMZ;
> +    env->fpscr |= FP_VXIMZ;
>      finish_invalid_op_arith(env, POWERPC_EXCP_FP_VXIMZ, set_fpcc, retaddr);
>  }
>  
> @@ -268,7 +268,7 @@ static void float_invalid_op_vximz(CPUPPCState *env, bool set_fpcc,
>  static void float_invalid_op_vxsqrt(CPUPPCState *env, bool set_fpcc,
>                                      uintptr_t retaddr)
>  {
> -    env->fpscr |= 1 << FPSCR_VXSQRT;
> +    env->fpscr |= FP_VXSQRT;
>      finish_invalid_op_arith(env, POWERPC_EXCP_FP_VXSQRT, set_fpcc, retaddr);
>  }
>  
> @@ -276,13 +276,13 @@ static void float_invalid_op_vxsqrt(CPUPPCState *env, bool set_fpcc,
>  static void float_invalid_op_vxvc(CPUPPCState *env, bool set_fpcc,
>                                    uintptr_t retaddr)
>  {
> -    env->fpscr |= 1 << FPSCR_VXVC;
> +    env->fpscr |= FP_VXVC;
>      if (set_fpcc) {
> -        env->fpscr &= ~(0xF << FPSCR_FPCC);
> -        env->fpscr |= 0x11 << FPSCR_FPCC;
> +        env->fpscr &= ~FP_FPCC;
> +        env->fpscr |= (FP_C | FP_FU);
>      }
>      /* Update the floating-point invalid operation summary */
> -    env->fpscr |= 1 << FPSCR_VX;
> +    env->fpscr |= FP_VX;
>      /* Update the floating-point exception summary */
>      env->fpscr |= FP_FX;
>      /* We must update the target FPR before raising the exception */
> @@ -292,7 +292,7 @@ static void float_invalid_op_vxvc(CPUPPCState *env, bool set_fpcc,
>          cs->exception_index = POWERPC_EXCP_PROGRAM;
>          env->error_code = POWERPC_EXCP_FP | POWERPC_EXCP_FP_VXVC;
>          /* Update the floating-point enabled exception summary */
> -        env->fpscr |= 1 << FPSCR_FEX;
> +        env->fpscr |= FP_FEX;
>          /* Exception is differed */
>      }
>  }
> @@ -301,12 +301,12 @@ static void float_invalid_op_vxvc(CPUPPCState *env, bool set_fpcc,
>  static void float_invalid_op_vxcvi(CPUPPCState *env, bool set_fpcc,
>                                     uintptr_t retaddr)
>  {
> -    env->fpscr |= 1 << FPSCR_VXCVI;
> -    env->fpscr &= ~((1 << FPSCR_FR) | (1 << FPSCR_FI));
> +    env->fpscr |= FP_VXCVI;
> +    env->fpscr &= ~(FP_FR | FP_FI);
>      if (fpscr_ve == 0) {
>          if (set_fpcc) {
> -            env->fpscr &= ~(0xF << FPSCR_FPCC);
> -            env->fpscr |= 0x11 << FPSCR_FPCC;
> +            env->fpscr &= ~FP_FPCC;
> +            env->fpscr |= (FP_C | FP_FU);
>          }
>      }
>      finish_invalid_op_excp(env, POWERPC_EXCP_FP_VXCVI, retaddr);
> @@ -314,13 +314,13 @@ static void float_invalid_op_vxcvi(CPUPPCState *env, bool set_fpcc,
>  
>  static inline void float_zero_divide_excp(CPUPPCState *env, uintptr_t raddr)
>  {
> -    env->fpscr |= 1 << FPSCR_ZX;
> -    env->fpscr &= ~((1 << FPSCR_FR) | (1 << FPSCR_FI));
> +    env->fpscr |= FP_ZX;
> +    env->fpscr &= ~(FP_FR | FP_FI);
>      /* Update the floating-point exception summary */
>      env->fpscr |= FP_FX;
>      if (fpscr_ze != 0) {
>          /* Update the floating-point enabled exception summary */
> -        env->fpscr |= 1 << FPSCR_FEX;
> +        env->fpscr |= FP_FEX;
>          if (fp_exceptions_enabled(env)) {
>              raise_exception_err_ra(env, POWERPC_EXCP_PROGRAM,
>                                     POWERPC_EXCP_FP | POWERPC_EXCP_FP_ZX,
> @@ -333,19 +333,19 @@ static inline void float_overflow_excp(CPUPPCState *env)
>  {
>      CPUState *cs = env_cpu(env);
>  
> -    env->fpscr |= 1 << FPSCR_OX;
> +    env->fpscr |= FP_OX;
>      /* Update the floating-point exception summary */
>      env->fpscr |= FP_FX;
>      if (fpscr_oe != 0) {
>          /* XXX: should adjust the result */
>          /* Update the floating-point enabled exception summary */
> -        env->fpscr |= 1 << FPSCR_FEX;
> +        env->fpscr |= FP_FEX;
>          /* We must update the target FPR before raising the exception */
>          cs->exception_index = POWERPC_EXCP_PROGRAM;
>          env->error_code = POWERPC_EXCP_FP | POWERPC_EXCP_FP_OX;
>      } else {
> -        env->fpscr |= 1 << FPSCR_XX;
> -        env->fpscr |= 1 << FPSCR_FI;
> +        env->fpscr |= FP_XX;
> +        env->fpscr |= FP_FI;
>      }
>  }
>  
> @@ -353,13 +353,13 @@ static inline void float_underflow_excp(CPUPPCState *env)
>  {
>      CPUState *cs = env_cpu(env);
>  
> -    env->fpscr |= 1 << FPSCR_UX;
> +    env->fpscr |= FP_UX;
>      /* Update the floating-point exception summary */
>      env->fpscr |= FP_FX;
>      if (fpscr_ue != 0) {
>          /* XXX: should adjust the result */
>          /* Update the floating-point enabled exception summary */
> -        env->fpscr |= 1 << FPSCR_FEX;
> +        env->fpscr |= FP_FEX;
>          /* We must update the target FPR before raising the exception */
>          cs->exception_index = POWERPC_EXCP_PROGRAM;
>          env->error_code = POWERPC_EXCP_FP | POWERPC_EXCP_FP_UX;
> @@ -370,13 +370,13 @@ static inline void float_inexact_excp(CPUPPCState *env)
>  {
>      CPUState *cs = env_cpu(env);
>  
> -    env->fpscr |= 1 << FPSCR_FI;
> -    env->fpscr |= 1 << FPSCR_XX;
> +    env->fpscr |= FP_FI;
> +    env->fpscr |= FP_XX;
>      /* Update the floating-point exception summary */
>      env->fpscr |= FP_FX;
>      if (fpscr_xe != 0) {
>          /* Update the floating-point enabled exception summary */
> -        env->fpscr |= 1 << FPSCR_FEX;
> +        env->fpscr |= FP_FEX;
>          /* We must update the target FPR before raising the exception */
>          cs->exception_index = POWERPC_EXCP_PROGRAM;
>          env->error_code = POWERPC_EXCP_FP | POWERPC_EXCP_FP_XX;
> @@ -433,7 +433,7 @@ void helper_fpscr_clrbit(CPUPPCState *env, uint32_t bit)
>          case FPSCR_VXCVI:
>              if (!fpscr_ix) {
>                  /* Set VX bit to zero */
> -                env->fpscr &= ~(1 << FPSCR_VX);
> +                env->fpscr &= ~FP_VX;
>              }
>              break;
>          case FPSCR_OX:
> @@ -447,7 +447,7 @@ void helper_fpscr_clrbit(CPUPPCState *env, uint32_t bit)
>          case FPSCR_XE:
>              if (!fpscr_eex) {
>                  /* Set the FEX bit */
> -                env->fpscr &= ~(1 << FPSCR_FEX);
> +                env->fpscr &= ~FP_FEX;
>              }
>              break;
>          default:
> @@ -504,7 +504,7 @@ void helper_fpscr_setbit(CPUPPCState *env, uint32_t bit)
>          case FPSCR_VXSOFT:
>          case FPSCR_VXSQRT:
>          case FPSCR_VXCVI:
> -            env->fpscr |= 1 << FPSCR_VX;
> +            env->fpscr |= FP_VX;
>              env->fpscr |= FP_FX;
>              if (fpscr_ve != 0) {
>                  goto raise_ve;
> @@ -580,7 +580,7 @@ void helper_fpscr_setbit(CPUPPCState *env, uint32_t bit)
>              break;
>          raise_excp:
>              /* Update the floating-point enabled exception summary */
> -            env->fpscr |= 1 << FPSCR_FEX;
> +            env->fpscr |= FP_FEX;
>              /* We have to update Rc1 before raising the exception */
>              cs->exception_index = POWERPC_EXCP_PROGRAM;
>              break;
> @@ -596,8 +596,8 @@ void helper_store_fpscr(CPUPPCState *env, uint64_t arg, uint32_t mask)
>  
>      prev = env->fpscr;
>      new = (target_ulong)arg;
> -    new &= ~0x60000000LL;
> -    new |= prev & 0x60000000LL;
> +    new &= ~(FP_FEX | FP_VX);
> +    new |= prev & (FP_FEX | FP_VX);
>      for (i = 0; i < sizeof(target_ulong) * 2; i++) {
>          if (mask & (1 << i)) {
>              env->fpscr &= ~(0xFLL << (4 * i));
> @@ -606,17 +606,17 @@ void helper_store_fpscr(CPUPPCState *env, uint64_t arg, uint32_t mask)
>      }
>      /* Update VX and FEX */
>      if (fpscr_ix != 0) {
> -        env->fpscr |= 1 << FPSCR_VX;
> +        env->fpscr |= FP_VX;
>      } else {
> -        env->fpscr &= ~(1 << FPSCR_VX);
> +        env->fpscr &= ~FP_VX;
>      }
>      if ((fpscr_ex & fpscr_eex) != 0) {
> -        env->fpscr |= 1 << FPSCR_FEX;
> +        env->fpscr |= FP_FEX;
>          cs->exception_index = POWERPC_EXCP_PROGRAM;
>          /* XXX: we should compute it properly */
>          env->error_code = POWERPC_EXCP_FP;
>      } else {
> -        env->fpscr &= ~(1 << FPSCR_FEX);
> +        env->fpscr &= ~FP_FEX;
>      }
>      fpscr_set_rounding_mode(env);
>  }
> @@ -639,7 +639,7 @@ static void do_float_check_status(CPUPPCState *env, uintptr_t raddr)
>      if (status & float_flag_inexact) {
>          float_inexact_excp(env);
>      } else {
> -        env->fpscr &= ~(1 << FPSCR_FI); /* clear the FPSCR[FI] bit */
> +        env->fpscr &= ~FP_FI; /* clear the FPSCR[FI] bit */
>      }
>  
>      if (cs->exception_index == POWERPC_EXCP_PROGRAM &&
> @@ -1138,8 +1138,8 @@ void helper_fcmpu(CPUPPCState *env, uint64_t arg1, uint64_t arg2,
>          ret = 0x02UL;
>      }
>  
> -    env->fpscr &= ~(0x0F << FPSCR_FPRF);
> -    env->fpscr |= ret << FPSCR_FPRF;
> +    env->fpscr &= ~FP_FPCC;
> +    env->fpscr |= ret << FPSCR_FPCC;
>      env->crf[crfD] = ret;
>      if (unlikely(ret == 0x01UL
>                   && (float64_is_signaling_nan(farg1.d, &env->fp_status) ||
> @@ -1169,9 +1169,9 @@ void helper_fcmpo(CPUPPCState *env, uint64_t arg1, uint64_t arg2,
>          ret = 0x02UL;
>      }
>  
> -    env->fpscr &= ~(0x0F << FPSCR_FPRF);
> -    env->fpscr |= ret << FPSCR_FPRF;
> -    env->crf[crfD] = ret;
> +    env->fpscr &= ~FP_FPCC;
> +    env->fpscr |= ret << FPSCR_FPCC;
> +    env->crf[crfD] = (uint32_t) ret;
>      if (unlikely(ret == 0x01UL)) {
>          float_invalid_op_vxvc(env, 1, GETPC());
>          if (float64_is_signaling_nan(farg1.d, &env->fp_status) ||
> @@ -2431,8 +2431,8 @@ void helper_xscmpexpdp(CPUPPCState *env, uint32_t opcode,
>          }
>      }
>  
> -    env->fpscr &= ~(0x0F << FPSCR_FPRF);
> -    env->fpscr |= cc << FPSCR_FPRF;
> +    env->fpscr &= ~FP_FPCC;
> +    env->fpscr |= cc << FPSCR_FPCC;
>      env->crf[BF(opcode)] = cc;
>  
>      do_float_check_status(env, GETPC());
> @@ -2460,8 +2460,8 @@ void helper_xscmpexpqp(CPUPPCState *env, uint32_t opcode,
>          }
>      }
>  
> -    env->fpscr &= ~(0x0F << FPSCR_FPRF);
> -    env->fpscr |= cc << FPSCR_FPRF;
> +    env->fpscr &= ~FP_FPCC;
> +    env->fpscr |= cc << FPSCR_FPCC;
>      env->crf[BF(opcode)] = cc;
>  
>      do_float_check_status(env, GETPC());
> @@ -2505,8 +2505,8 @@ void helper_##op(CPUPPCState *env, uint32_t opcode,                      \
>          cc |= CRF_EQ;                                                    \
>      }                                                                    \
>                                                                           \
> -    env->fpscr &= ~(0x0F << FPSCR_FPRF);                                 \
> -    env->fpscr |= cc << FPSCR_FPRF;                                      \
> +    env->fpscr &= ~FP_FPCC;                                              \
> +    env->fpscr |= cc << FPSCR_FPCC;                                      \
>      env->crf[BF(opcode)] = cc;                                           \
>                                                                           \
>      do_float_check_status(env, GETPC());                                 \
> @@ -2553,8 +2553,8 @@ void helper_##op(CPUPPCState *env, uint32_t opcode,                     \
>          cc |= CRF_EQ;                                                   \
>      }                                                                   \
>                                                                          \
> -    env->fpscr &= ~(0x0F << FPSCR_FPRF);                                \
> -    env->fpscr |= cc << FPSCR_FPRF;                                     \
> +    env->fpscr &= ~FP_FPCC;                                             \
> +    env->fpscr |= cc << FPSCR_FPCC;                                     \
>      env->crf[BF(opcode)] = cc;                                          \
>                                                                          \
>      do_float_check_status(env, GETPC());                                \
> @@ -3242,8 +3242,8 @@ void helper_##op(CPUPPCState *env, uint32_t opcode)         \
>                                                              \
>          if (scrf) {                                         \
>              cc = sign << CRF_LT_BIT | match << CRF_EQ_BIT;  \
> -            env->fpscr &= ~(0x0F << FPSCR_FPRF);            \
> -            env->fpscr |= cc << FPSCR_FPRF;                 \
> +            env->fpscr &= ~FP_FPCC;                         \
> +            env->fpscr |= cc << FPSCR_FPCC;                 \
>              env->crf[BF(opcode)] = cc;                      \
>          } else {                                            \
>              t.tfld = match ? fld_max : 0;                   \
> @@ -3286,8 +3286,8 @@ void helper_xststdcsp(CPUPPCState *env, uint32_t opcode, ppc_vsr_t *xb)
>                               &env->fp_status), &env->fp_status);
>  
>      cc = sign << CRF_LT_BIT | match << CRF_EQ_BIT | not_sp << CRF_SO_BIT;
> -    env->fpscr &= ~(0x0F << FPSCR_FPRF);
> -    env->fpscr |= cc << FPSCR_FPRF;
> +    env->fpscr &= ~FP_FPCC;
> +    env->fpscr |= cc << FPSCR_FPCC;
>      env->crf[BF(opcode)] = cc;
>  }
>  

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson

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      parent reply	other threads:[~2019-09-19  6:52 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-09-18 14:32 [Qemu-devel] [PATCH] ppc: Use FPSCR defines instead of constants Paul A. Clarke
2019-09-18 15:09 ` Richard Henderson
2019-09-19  6:30 ` David Gibson [this message]

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