From: "Bruno Larsen (billionai)" <bruno.larsen@eldorado.org.br>
To: qemu-devel@nongnu.org
Cc: farosas@linux.ibm.com, richard.henderson@linaro.org,
luis.pires@eldorado.org.br, lucas.araujo@eldorado.org.br,
fernando.valle@eldorado.org.br, qemu-ppc@nongnu.org,
matheus.ferst@eldorado.org.br, david@gibson.dropbear.id.au
Subject: [PATCH v3 4/9] target/ppc: overhauled and moved logic of storing fpscr
Date: Fri, 21 May 2021 17:17:54 -0300 [thread overview]
Message-ID: <20210521201759.85475-5-bruno.larsen@eldorado.org.br> (raw)
In-Reply-To: <20210521201759.85475-1-bruno.larsen@eldorado.org.br>
Followed the suggested overhaul to store_fpscr logic, and moved it to
cpu.c where it can be accessed in !TCG builds.
The overhaul was suggesting because storing a value to fpscr should
never raise an exception, so we could remove all the mess that happened
with POWERPC_EXCP_FP.
We also moved fpscr_set_rounding_mode into cpu.c as it could now be moved
there, and it is needed when a value for the fpscr is being stored
directly.
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Bruno Larsen (billionai) <bruno.larsen@eldorado.org.br>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
---
target/ppc/cpu.c | 43 ++++++++
target/ppc/cpu.h | 12 +-
target/ppc/fpu_helper.c | 238 +++-------------------------------------
target/ppc/gdbstub.c | 6 +-
4 files changed, 65 insertions(+), 234 deletions(-)
diff --git a/target/ppc/cpu.c b/target/ppc/cpu.c
index c8e87e30f1..19d67b5b07 100644
--- a/target/ppc/cpu.c
+++ b/target/ppc/cpu.c
@@ -25,6 +25,7 @@
#include "fpu/softfloat-helpers.h"
#include "mmu-hash64.h"
#include "helper_regs.h"
+#include "sysemu/tcg.h"
target_ulong cpu_read_xer(CPUPPCState *env)
{
@@ -109,3 +110,45 @@ void ppc_store_lpcr(PowerPCCPU *cpu, target_ulong val)
/* The gtse bit affects hflags */
hreg_compute_hflags(env);
}
+
+static inline void fpscr_set_rounding_mode(CPUPPCState *env)
+{
+ int rnd_type;
+
+ /* Set rounding mode */
+ switch (fpscr_rn) {
+ case 0:
+ /* Best approximation (round to nearest) */
+ rnd_type = float_round_nearest_even;
+ break;
+ case 1:
+ /* Smaller magnitude (round toward zero) */
+ rnd_type = float_round_to_zero;
+ break;
+ case 2:
+ /* Round toward +infinite */
+ rnd_type = float_round_up;
+ break;
+ default:
+ case 3:
+ /* Round toward -infinite */
+ rnd_type = float_round_down;
+ break;
+ }
+ set_float_rounding_mode(rnd_type, &env->fp_status);
+}
+
+void ppc_store_fpscr(CPUPPCState *env, target_ulong val)
+{
+ val &= ~(FP_VX | FP_FEX);
+ if (val & FPSCR_IX) {
+ val |= FP_VX;
+ }
+ if ((val >> FPSCR_XX) & (val >> FPSCR_XE) & 0x1f) {
+ val |= FP_FEX;
+ }
+ env->fpscr = val;
+ if (tcg_enabled()) {
+ fpscr_set_rounding_mode(env);
+ }
+}
diff --git a/target/ppc/cpu.h b/target/ppc/cpu.h
index cab33a3680..203f07e48e 100644
--- a/target/ppc/cpu.h
+++ b/target/ppc/cpu.h
@@ -675,11 +675,11 @@ enum {
#define fpscr_ni (((env->fpscr) >> FPSCR_NI) & 0x1)
#define fpscr_rn (((env->fpscr) >> FPSCR_RN0) & 0x3)
/* Invalid operation exception summary */
-#define fpscr_ix ((env->fpscr) & ((1 << FPSCR_VXSNAN) | (1 << FPSCR_VXISI) | \
- (1 << FPSCR_VXIDI) | (1 << FPSCR_VXZDZ) | \
- (1 << FPSCR_VXIMZ) | (1 << FPSCR_VXVC) | \
- (1 << FPSCR_VXSOFT) | (1 << FPSCR_VXSQRT) | \
- (1 << FPSCR_VXCVI)))
+#define FPSCR_IX ((1 << FPSCR_VXSNAN) | (1 << FPSCR_VXISI) | \
+ (1 << FPSCR_VXIDI) | (1 << FPSCR_VXZDZ) | \
+ (1 << FPSCR_VXIMZ) | (1 << FPSCR_VXVC) | \
+ (1 << FPSCR_VXSOFT) | (1 << FPSCR_VXSQRT) | \
+ (1 << FPSCR_VXCVI))
/* exception summary */
#define fpscr_ex (((env->fpscr) >> FPSCR_XX) & 0x1F)
/* enabled exception summary */
@@ -1334,7 +1334,7 @@ void cpu_ppc_set_vhyp(PowerPCCPU *cpu, PPCVirtualHypervisor *vhyp);
#endif
#endif
-void store_fpscr(CPUPPCState *env, uint64_t arg, uint32_t mask);
+void ppc_store_fpscr(CPUPPCState *env, target_ulong val);
void helper_hfscr_facility_check(CPUPPCState *env, uint32_t bit,
const char *caller, uint32_t cause);
diff --git a/target/ppc/fpu_helper.c b/target/ppc/fpu_helper.c
index a4a283df2b..0f4074fc7e 100644
--- a/target/ppc/fpu_helper.c
+++ b/target/ppc/fpu_helper.c
@@ -383,247 +383,35 @@ static inline void float_inexact_excp(CPUPPCState *env)
}
}
-static inline void fpscr_set_rounding_mode(CPUPPCState *env)
-{
- int rnd_type;
-
- /* Set rounding mode */
- switch (fpscr_rn) {
- case 0:
- /* Best approximation (round to nearest) */
- rnd_type = float_round_nearest_even;
- break;
- case 1:
- /* Smaller magnitude (round toward zero) */
- rnd_type = float_round_to_zero;
- break;
- case 2:
- /* Round toward +infinite */
- rnd_type = float_round_up;
- break;
- default:
- case 3:
- /* Round toward -infinite */
- rnd_type = float_round_down;
- break;
- }
- set_float_rounding_mode(rnd_type, &env->fp_status);
-}
-
void helper_fpscr_clrbit(CPUPPCState *env, uint32_t bit)
{
- int prev;
-
- prev = (env->fpscr >> bit) & 1;
- env->fpscr &= ~(1 << bit);
- if (prev == 1) {
- switch (bit) {
- case FPSCR_RN1:
- case FPSCR_RN0:
- fpscr_set_rounding_mode(env);
- break;
- case FPSCR_VXSNAN:
- case FPSCR_VXISI:
- case FPSCR_VXIDI:
- case FPSCR_VXZDZ:
- case FPSCR_VXIMZ:
- case FPSCR_VXVC:
- case FPSCR_VXSOFT:
- case FPSCR_VXSQRT:
- case FPSCR_VXCVI:
- if (!fpscr_ix) {
- /* Set VX bit to zero */
- env->fpscr &= ~FP_VX;
- }
- break;
- case FPSCR_OX:
- case FPSCR_UX:
- case FPSCR_ZX:
- case FPSCR_XX:
- case FPSCR_VE:
- case FPSCR_OE:
- case FPSCR_UE:
- case FPSCR_ZE:
- case FPSCR_XE:
- if (!fpscr_eex) {
- /* Set the FEX bit */
- env->fpscr &= ~FP_FEX;
- }
- break;
- default:
- break;
- }
+ uint32_t mask = 1u << bit;
+ if (env->fpscr & mask) {
+ ppc_store_fpscr(env, env->fpscr & ~mask);
}
}
void helper_fpscr_setbit(CPUPPCState *env, uint32_t bit)
{
- CPUState *cs = env_cpu(env);
- int prev;
-
- prev = (env->fpscr >> bit) & 1;
- env->fpscr |= 1 << bit;
- if (prev == 0) {
- switch (bit) {
- case FPSCR_VX:
- env->fpscr |= FP_FX;
- if (fpscr_ve) {
- goto raise_ve;
- }
- break;
- case FPSCR_OX:
- env->fpscr |= FP_FX;
- if (fpscr_oe) {
- goto raise_oe;
- }
- break;
- case FPSCR_UX:
- env->fpscr |= FP_FX;
- if (fpscr_ue) {
- goto raise_ue;
- }
- break;
- case FPSCR_ZX:
- env->fpscr |= FP_FX;
- if (fpscr_ze) {
- goto raise_ze;
- }
- break;
- case FPSCR_XX:
- env->fpscr |= FP_FX;
- if (fpscr_xe) {
- goto raise_xe;
- }
- break;
- case FPSCR_VXSNAN:
- case FPSCR_VXISI:
- case FPSCR_VXIDI:
- case FPSCR_VXZDZ:
- case FPSCR_VXIMZ:
- case FPSCR_VXVC:
- case FPSCR_VXSOFT:
- case FPSCR_VXSQRT:
- case FPSCR_VXCVI:
- env->fpscr |= FP_VX;
- env->fpscr |= FP_FX;
- if (fpscr_ve != 0) {
- goto raise_ve;
- }
- break;
- case FPSCR_VE:
- if (fpscr_vx != 0) {
- raise_ve:
- env->error_code = POWERPC_EXCP_FP;
- if (fpscr_vxsnan) {
- env->error_code |= POWERPC_EXCP_FP_VXSNAN;
- }
- if (fpscr_vxisi) {
- env->error_code |= POWERPC_EXCP_FP_VXISI;
- }
- if (fpscr_vxidi) {
- env->error_code |= POWERPC_EXCP_FP_VXIDI;
- }
- if (fpscr_vxzdz) {
- env->error_code |= POWERPC_EXCP_FP_VXZDZ;
- }
- if (fpscr_vximz) {
- env->error_code |= POWERPC_EXCP_FP_VXIMZ;
- }
- if (fpscr_vxvc) {
- env->error_code |= POWERPC_EXCP_FP_VXVC;
- }
- if (fpscr_vxsoft) {
- env->error_code |= POWERPC_EXCP_FP_VXSOFT;
- }
- if (fpscr_vxsqrt) {
- env->error_code |= POWERPC_EXCP_FP_VXSQRT;
- }
- if (fpscr_vxcvi) {
- env->error_code |= POWERPC_EXCP_FP_VXCVI;
- }
- goto raise_excp;
- }
- break;
- case FPSCR_OE:
- if (fpscr_ox != 0) {
- raise_oe:
- env->error_code = POWERPC_EXCP_FP | POWERPC_EXCP_FP_OX;
- goto raise_excp;
- }
- break;
- case FPSCR_UE:
- if (fpscr_ux != 0) {
- raise_ue:
- env->error_code = POWERPC_EXCP_FP | POWERPC_EXCP_FP_UX;
- goto raise_excp;
- }
- break;
- case FPSCR_ZE:
- if (fpscr_zx != 0) {
- raise_ze:
- env->error_code = POWERPC_EXCP_FP | POWERPC_EXCP_FP_ZX;
- goto raise_excp;
- }
- break;
- case FPSCR_XE:
- if (fpscr_xx != 0) {
- raise_xe:
- env->error_code = POWERPC_EXCP_FP | POWERPC_EXCP_FP_XX;
- goto raise_excp;
- }
- break;
- case FPSCR_RN1:
- case FPSCR_RN0:
- fpscr_set_rounding_mode(env);
- break;
- default:
- break;
- raise_excp:
- /* Update the floating-point enabled exception summary */
- env->fpscr |= FP_FEX;
- /* We have to update Rc1 before raising the exception */
- cs->exception_index = POWERPC_EXCP_PROGRAM;
- break;
- }
+ uint32_t mask = 1u << bit;
+ if (!(env->fpscr & mask)) {
+ ppc_store_fpscr(env, env->fpscr | mask);
}
}
-void helper_store_fpscr(CPUPPCState *env, uint64_t arg, uint32_t mask)
+void helper_store_fpscr(CPUPPCState *env, uint64_t val, uint32_t nibbles)
{
- CPUState *cs = env_cpu(env);
- target_ulong prev, new;
+ target_ulong mask = 0;
int i;
- prev = env->fpscr;
- new = (target_ulong)arg;
- new &= ~(FP_FEX | FP_VX);
- new |= prev & (FP_FEX | FP_VX);
+ /* TODO: push this extension back to translation time */
for (i = 0; i < sizeof(target_ulong) * 2; i++) {
- if (mask & (1 << i)) {
- env->fpscr &= ~(0xFLL << (4 * i));
- env->fpscr |= new & (0xFLL << (4 * i));
+ if (nibbles & (1 << i)) {
+ mask |= (target_ulong) 0xf << (4 * i);
}
}
- /* Update VX and FEX */
- if (fpscr_ix != 0) {
- env->fpscr |= FP_VX;
- } else {
- env->fpscr &= ~FP_VX;
- }
- if ((fpscr_ex & fpscr_eex) != 0) {
- 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 &= ~FP_FEX;
- }
- fpscr_set_rounding_mode(env);
-}
-
-void store_fpscr(CPUPPCState *env, uint64_t arg, uint32_t mask)
-{
- helper_store_fpscr(env, arg, mask);
+ val = (val & mask) | (env->fpscr & ~mask);
+ ppc_store_fpscr(env, val);
}
static void do_float_check_status(CPUPPCState *env, uintptr_t raddr)
diff --git a/target/ppc/gdbstub.c b/target/ppc/gdbstub.c
index 9339e7eafe..c7d866cfcc 100644
--- a/target/ppc/gdbstub.c
+++ b/target/ppc/gdbstub.c
@@ -272,7 +272,7 @@ int ppc_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n)
break;
case 70:
/* fpscr */
- store_fpscr(env, ldtul_p(mem_buf), 0xffffffff);
+ ppc_store_fpscr(env, ldtul_p(mem_buf));
break;
}
}
@@ -322,7 +322,7 @@ int ppc_cpu_gdb_write_register_apple(CPUState *cs, uint8_t *mem_buf, int n)
break;
case 70 + 32:
/* fpscr */
- store_fpscr(env, ldq_p(mem_buf), 0xffffffff);
+ ppc_store_fpscr(env, ldq_p(mem_buf));
break;
}
}
@@ -475,7 +475,7 @@ static int gdb_set_float_reg(CPUPPCState *env, uint8_t *mem_buf, int n)
}
if (n == 32) {
ppc_maybe_bswap_register(env, mem_buf, 4);
- store_fpscr(env, ldl_p(mem_buf), 0xffffffff);
+ ppc_store_fpscr(env, ldl_p(mem_buf));
return 4;
}
return 0;
--
2.17.1
next prev parent reply other threads:[~2021-05-21 20:21 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-05-21 20:17 [PATCH v3 0/9] target/ppc: add support to disable-tcg Bruno Larsen (billionai)
2021-05-21 20:17 ` [PATCH v3 1/9] target/ppc: cleaned error_report from ppc_store_sdr1 Bruno Larsen (billionai)
2021-05-24 2:36 ` David Gibson
2021-05-21 20:17 ` [PATCH v3 2/9] target/ppc: moved ppc_store_lpcr and ppc_store_msr to cpu.c Bruno Larsen (billionai)
2021-05-24 2:37 ` David Gibson
2021-05-21 20:17 ` [PATCH v3 3/9] target/ppc: reduce usage of fpscr_set_rounding_mode Bruno Larsen (billionai)
2021-05-24 2:38 ` David Gibson
2021-05-21 20:17 ` Bruno Larsen (billionai) [this message]
2021-05-24 2:41 ` [PATCH v3 4/9] target/ppc: overhauled and moved logic of storing fpscr David Gibson
2021-05-25 2:01 ` Richard Henderson
2021-05-25 3:15 ` David Gibson
2021-05-21 20:17 ` [PATCH v3 5/9] target/ppc: removed unnecessary inclusion of helper-proto.h Bruno Larsen (billionai)
2021-05-24 2:41 ` David Gibson
2021-05-21 20:17 ` [PATCH v3 6/9] target/ppc: moved ppc_cpu_do_interrupt to cpu.c Bruno Larsen (billionai)
2021-05-24 2:57 ` David Gibson
2021-05-25 2:11 ` Richard Henderson
2021-05-21 20:17 ` [PATCH v3 7/9] target/ppc: Added options to disable many TCG-only functions Bruno Larsen (billionai)
2021-05-24 3:01 ` David Gibson
2021-05-21 20:17 ` [PATCH v3 8/9] target/ppc: created tcg-stub.c file Bruno Larsen (billionai)
2021-05-24 3:02 ` David Gibson
2021-05-24 12:54 ` Bruno Piazera Larsen
2021-05-21 20:17 ` [PATCH v3 9/9] target/ppc: updated meson.build to support disable-tcg Bruno Larsen (billionai)
2021-05-25 2:13 ` Richard Henderson
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210521201759.85475-5-bruno.larsen@eldorado.org.br \
--to=bruno.larsen@eldorado.org.br \
--cc=david@gibson.dropbear.id.au \
--cc=farosas@linux.ibm.com \
--cc=fernando.valle@eldorado.org.br \
--cc=lucas.araujo@eldorado.org.br \
--cc=luis.pires@eldorado.org.br \
--cc=matheus.ferst@eldorado.org.br \
--cc=qemu-devel@nongnu.org \
--cc=qemu-ppc@nongnu.org \
--cc=richard.henderson@linaro.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.