Re: [PATCH v2 05/45] target/hppa: Allow prior nullification in do_ibranch

2024-05-14 Thread Helge Deller
* Richard Henderson :
> Simplify the function by not attempting a conditional move
> on the branch destination -- just use nullify_over normally.
> 
> Signed-off-by: Richard Henderson 

Reviewed-by: Helge Deller 

> ---
>  target/hppa/translate.c | 73 +++--
>  1 file changed, 20 insertions(+), 53 deletions(-)
> 
> diff --git a/target/hppa/translate.c b/target/hppa/translate.c
> index 4c42b518c5..140dfb747a 100644
> --- a/target/hppa/translate.c
> +++ b/target/hppa/translate.c
> @@ -1871,17 +1871,15 @@ static bool do_cbranch(DisasContext *ctx, int64_t 
> disp, bool is_n,
>  static bool do_ibranch(DisasContext *ctx, TCGv_i64 dest,
> unsigned link, bool is_n)
>  {
> -TCGv_i64 a0, a1, next, tmp;
> -TCGCond c;
> +TCGv_i64 next;
>  
> -assert(ctx->null_lab == NULL);
> +if (ctx->null_cond.c == TCG_COND_NEVER && ctx->null_lab == NULL) {
> +next = tcg_temp_new_i64();
> +tcg_gen_mov_i64(next, dest);
>  
> -if (ctx->null_cond.c == TCG_COND_NEVER) {
>  if (link != 0) {
>  copy_iaoq_entry(ctx, cpu_gr[link], ctx->iaoq_n, ctx->iaoq_n_var);
>  }
> -next = tcg_temp_new_i64();
> -tcg_gen_mov_i64(next, dest);
>  if (is_n) {
>  if (use_nullify_skip(ctx)) {
>  copy_iaoq_entry(ctx, cpu_iaoq_f, -1, next);
> @@ -1895,60 +1893,29 @@ static bool do_ibranch(DisasContext *ctx, TCGv_i64 
> dest,
>  }
>  ctx->iaoq_n = -1;
>  ctx->iaoq_n_var = next;
> -} else if (is_n && use_nullify_skip(ctx)) {
> -/* The (conditional) branch, B, nullifies the next insn, N,
> -   and we're allowed to skip execution N (no single-step or
> -   tracepoint in effect).  Since the goto_ptr that we must use
> -   for the indirect branch consumes no special resources, we
> -   can (conditionally) skip B and continue execution.  */
> -/* The use_nullify_skip test implies we have a known control path.  
> */
> -tcg_debug_assert(ctx->iaoq_b != -1);
> -tcg_debug_assert(ctx->iaoq_n != -1);
> +return true;
> +}
>  
> -/* We do have to handle the non-local temporary, DEST, before
> -   branching.  Since IOAQ_F is not really live at this point, we
> -   can simply store DEST optimistically.  Similarly with IAOQ_B.  */
> +nullify_over(ctx);
> +
> +if (is_n && use_nullify_skip(ctx)) {
>  copy_iaoq_entry(ctx, cpu_iaoq_f, -1, dest);
>  next = tcg_temp_new_i64();
>  tcg_gen_addi_i64(next, dest, 4);
>  copy_iaoq_entry(ctx, cpu_iaoq_b, -1, next);
> -
> -nullify_over(ctx);
> -if (link != 0) {
> -copy_iaoq_entry(ctx, cpu_gr[link], ctx->iaoq_n, ctx->iaoq_n_var);
> -}
> -tcg_gen_lookup_and_goto_ptr();
> -return nullify_end(ctx);
> +nullify_set(ctx, 0);
>  } else {
> -c = ctx->null_cond.c;
> -a0 = ctx->null_cond.a0;
> -a1 = ctx->null_cond.a1;
> -
> -tmp = tcg_temp_new_i64();
> -next = tcg_temp_new_i64();
> -
> -copy_iaoq_entry(ctx, tmp, ctx->iaoq_n, ctx->iaoq_n_var);
> -tcg_gen_movcond_i64(c, next, a0, a1, tmp, dest);
> -ctx->iaoq_n = -1;
> -ctx->iaoq_n_var = next;
> -
> -if (link != 0) {
> -tcg_gen_movcond_i64(c, cpu_gr[link], a0, a1, cpu_gr[link], tmp);
> -}
> -
> -if (is_n) {
> -/* The branch nullifies the next insn, which means the state of N
> -   after the branch is the inverse of the state of N that applied
> -   to the branch.  */
> -tcg_gen_setcond_i64(tcg_invert_cond(c), cpu_psw_n, a0, a1);
> -cond_free(>null_cond);
> -ctx->null_cond = cond_make_n();
> -ctx->psw_n_nonzero = true;
> -} else {
> -cond_free(>null_cond);
> -}
> +copy_iaoq_entry(ctx, cpu_iaoq_f, ctx->iaoq_b, cpu_iaoq_b);
> +copy_iaoq_entry(ctx, cpu_iaoq_b, -1, dest);
> +nullify_set(ctx, is_n);
>  }
> -return true;
> +if (link != 0) {
> +copy_iaoq_entry(ctx, cpu_gr[link], ctx->iaoq_n, ctx->iaoq_n_var);
> +}
> +
> +tcg_gen_lookup_and_goto_ptr();
> +ctx->base.is_jmp = DISAS_NORETURN;
> +return nullify_end(ctx);
>  }
>  
>  /* Implement
> -- 
> 2.34.1
> 



[PATCH v2 05/45] target/hppa: Allow prior nullification in do_ibranch

2024-05-13 Thread Richard Henderson
Simplify the function by not attempting a conditional move
on the branch destination -- just use nullify_over normally.

Signed-off-by: Richard Henderson 
---
 target/hppa/translate.c | 73 +++--
 1 file changed, 20 insertions(+), 53 deletions(-)

diff --git a/target/hppa/translate.c b/target/hppa/translate.c
index 4c42b518c5..140dfb747a 100644
--- a/target/hppa/translate.c
+++ b/target/hppa/translate.c
@@ -1871,17 +1871,15 @@ static bool do_cbranch(DisasContext *ctx, int64_t disp, 
bool is_n,
 static bool do_ibranch(DisasContext *ctx, TCGv_i64 dest,
unsigned link, bool is_n)
 {
-TCGv_i64 a0, a1, next, tmp;
-TCGCond c;
+TCGv_i64 next;
 
-assert(ctx->null_lab == NULL);
+if (ctx->null_cond.c == TCG_COND_NEVER && ctx->null_lab == NULL) {
+next = tcg_temp_new_i64();
+tcg_gen_mov_i64(next, dest);
 
-if (ctx->null_cond.c == TCG_COND_NEVER) {
 if (link != 0) {
 copy_iaoq_entry(ctx, cpu_gr[link], ctx->iaoq_n, ctx->iaoq_n_var);
 }
-next = tcg_temp_new_i64();
-tcg_gen_mov_i64(next, dest);
 if (is_n) {
 if (use_nullify_skip(ctx)) {
 copy_iaoq_entry(ctx, cpu_iaoq_f, -1, next);
@@ -1895,60 +1893,29 @@ static bool do_ibranch(DisasContext *ctx, TCGv_i64 dest,
 }
 ctx->iaoq_n = -1;
 ctx->iaoq_n_var = next;
-} else if (is_n && use_nullify_skip(ctx)) {
-/* The (conditional) branch, B, nullifies the next insn, N,
-   and we're allowed to skip execution N (no single-step or
-   tracepoint in effect).  Since the goto_ptr that we must use
-   for the indirect branch consumes no special resources, we
-   can (conditionally) skip B and continue execution.  */
-/* The use_nullify_skip test implies we have a known control path.  */
-tcg_debug_assert(ctx->iaoq_b != -1);
-tcg_debug_assert(ctx->iaoq_n != -1);
+return true;
+}
 
-/* We do have to handle the non-local temporary, DEST, before
-   branching.  Since IOAQ_F is not really live at this point, we
-   can simply store DEST optimistically.  Similarly with IAOQ_B.  */
+nullify_over(ctx);
+
+if (is_n && use_nullify_skip(ctx)) {
 copy_iaoq_entry(ctx, cpu_iaoq_f, -1, dest);
 next = tcg_temp_new_i64();
 tcg_gen_addi_i64(next, dest, 4);
 copy_iaoq_entry(ctx, cpu_iaoq_b, -1, next);
-
-nullify_over(ctx);
-if (link != 0) {
-copy_iaoq_entry(ctx, cpu_gr[link], ctx->iaoq_n, ctx->iaoq_n_var);
-}
-tcg_gen_lookup_and_goto_ptr();
-return nullify_end(ctx);
+nullify_set(ctx, 0);
 } else {
-c = ctx->null_cond.c;
-a0 = ctx->null_cond.a0;
-a1 = ctx->null_cond.a1;
-
-tmp = tcg_temp_new_i64();
-next = tcg_temp_new_i64();
-
-copy_iaoq_entry(ctx, tmp, ctx->iaoq_n, ctx->iaoq_n_var);
-tcg_gen_movcond_i64(c, next, a0, a1, tmp, dest);
-ctx->iaoq_n = -1;
-ctx->iaoq_n_var = next;
-
-if (link != 0) {
-tcg_gen_movcond_i64(c, cpu_gr[link], a0, a1, cpu_gr[link], tmp);
-}
-
-if (is_n) {
-/* The branch nullifies the next insn, which means the state of N
-   after the branch is the inverse of the state of N that applied
-   to the branch.  */
-tcg_gen_setcond_i64(tcg_invert_cond(c), cpu_psw_n, a0, a1);
-cond_free(>null_cond);
-ctx->null_cond = cond_make_n();
-ctx->psw_n_nonzero = true;
-} else {
-cond_free(>null_cond);
-}
+copy_iaoq_entry(ctx, cpu_iaoq_f, ctx->iaoq_b, cpu_iaoq_b);
+copy_iaoq_entry(ctx, cpu_iaoq_b, -1, dest);
+nullify_set(ctx, is_n);
 }
-return true;
+if (link != 0) {
+copy_iaoq_entry(ctx, cpu_gr[link], ctx->iaoq_n, ctx->iaoq_n_var);
+}
+
+tcg_gen_lookup_and_goto_ptr();
+ctx->base.is_jmp = DISAS_NORETURN;
+return nullify_end(ctx);
 }
 
 /* Implement
-- 
2.34.1