xemu/target
Taylor Simpson d54c56156f Hexagon (target/hexagon) Short-circuit packet register writes
In certain cases, we can avoid the overhead of writing to hex_new_value
and write directly to hex_gpr.  We add need_commit field to DisasContext
indicating if the end-of-packet commit is needed.  If it is not needed,
get_result_gpr() and get_result_gpr_pair() can return hex_gpr.

We pass the ctx->need_commit to helpers when needed.

Finally, we can early-exit from gen_reg_writes during packet commit.

There are a few instructions whose semantics write to the result before
reading all the inputs.  Therefore, the idef-parser generated code is
incompatible with short-circuit.  We tell idef-parser to skip them.

For debugging purposes, we add a cpu property to turn off short-circuit.
When the short-circuit property is false, we skip the analysis and force
the end-of-packet commit.

Here's a simple example of the TCG generated for
0x004000b4:  0x7800c020 {       R0 = #0x1 }

BEFORE:
 ---- 004000b4
 movi_i32 new_r0,$0x1
 mov_i32 r0,new_r0

AFTER:
 ---- 004000b4
 movi_i32 r0,$0x1

This patch reintroduces a use of check_for_attrib, so we remove the
G_GNUC_UNUSED added earlier in this series.

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Brian Cain <bcain@quicinc.com>
Message-Id: <20230427230012.3800327-12-tsimpson@quicinc.com>
2023-05-18 12:40:52 -07:00
..
alpha target/alpha: Use MO_ALIGN where required 2023-05-05 17:05:58 +01:00
arm target/arm: Add compile time asserts to load/store_cpu_field macros 2023-05-02 15:47:41 +01:00
avr target/avr: Finish conversion to tcg_gen_qemu_{ld,st}_* 2023-05-05 17:05:28 +01:00
cris target/cris: Finish conversion to tcg_gen_qemu_{ld,st}_* 2023-05-05 17:05:28 +01:00
hexagon Hexagon (target/hexagon) Short-circuit packet register writes 2023-05-18 12:40:52 -07:00
hppa target/hppa: Use MO_ALIGN for system UNALIGN() 2023-05-05 17:05:58 +01:00
i386 target/i386: Add EPYC-Genoa model to support Zen 4 processor series 2023-05-08 16:35:30 +02:00
loongarch target/loongarch: Do not include tcg-ldst.h 2023-05-11 09:53:41 +01:00
m68k target/m68k: Fix gen_load_fp for OS_LONG 2023-05-11 09:49:25 +01:00
microblaze target/microblaze: Remove `NB_MMU_MODES` define 2023-03-13 06:44:37 -07:00
mips target/mips: Use MO_ALIGN instead of 0 2023-05-11 09:53:41 +01:00
nios2 target/nios2: Remove TARGET_ALIGNED_ONLY 2023-05-11 09:53:41 +01:00
openrisc target/openrisc: Remove `NB_MMU_MODES` define 2023-03-13 06:44:37 -07:00
ppc tcg: ppc64: Fix mask generation for vextractdm 2023-05-05 12:34:22 -03:00
riscv target/riscv: add Ventana's Veyron V1 CPU 2023-05-05 10:49:50 +10:00
rx target/rx: Avoid tcg_const_i32 2023-03-13 06:44:37 -07:00
s390x target/s390x: Finish conversion to tcg_gen_qemu_{ld, st}_* 2023-05-05 17:05:28 +01:00
sh4 target/sh4: Use MO_ALIGN where required 2023-05-11 09:53:41 +01:00
sparc target/sparc: Use cpu_ld*_code_mmu 2023-05-05 17:09:47 +01:00
tricore target/tricore: Use min/max for saturate 2023-03-13 07:03:39 -07:00
xtensa target/xtensa: Finish conversion to tcg_gen_qemu_{ld, st}_* 2023-05-05 17:05:29 +01:00
Kconfig hw/loongarch: Add support loongson3 virt machine type. 2022-06-06 18:09:03 +00:00
meson.build target/loongarch: Add target build suport 2022-06-06 18:09:03 +00:00