Skip to content

[mono][interp] Lower div.un to shr.un.imm #83498

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
BrzVlad merged 2 commits into from
Mar 16, 2023
Merged

[mono][interp] Lower div.un to shr.un.imm #83498

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
f766a8d
[mono][interp] Remove redundant opcode
BrzVlad Mar 14, 2023
62f98dd
[mono][interp] Lower div.un to shr.un
BrzVlad Mar 16, 2023
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
5 changes: 0 additions & 5 deletions src/mono/mono/mini/interp/interp.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -5963,11 +5963,6 @@ MINT_IN_CASE(MINT_BRTRUE_I8_SP) ZEROP_SP(gint64, !=); MINT_IN_BREAK;
ip += 5;
MINT_IN_BREAK;
}
MINT_IN_CASE(MINT_INTRINS_UNSAFE_BYTE_OFFSET) {
LOCAL_VAR (ip [1], mono_u) = LOCAL_VAR (ip [3], guint8*) - LOCAL_VAR (ip [2], guint8*);
ip += 4;
MINT_IN_BREAK;
}
MINT_IN_CASE(MINT_INTRINS_RUNTIMEHELPERS_OBJECT_HAS_COMPONENT_SIZE) {
MonoObject *obj = LOCAL_VAR (ip [2], MonoObject*);
LOCAL_VAR (ip [1], gint32) = (obj->vtable->flags & MONO_VT_FLAG_ARRAY_OR_STRING) != 0;
Expand Down
1 change: 0 additions & 1 deletion src/mono/mono/mini/interp/jiterpreter.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -666,7 +666,6 @@ jiterp_should_abort_trace (InterpInst *ins, gboolean *inside_branch_block)
case MINT_GETITEM_SPAN:
case MINT_GETITEM_LOCALSPAN:
case MINT_INTRINS_SPAN_CTOR:
case MINT_INTRINS_UNSAFE_BYTE_OFFSET:
case MINT_INTRINS_GET_TYPE:
case MINT_INTRINS_MEMORYMARSHAL_GETARRAYDATAREF:
case MINT_CASTCLASS:
Expand Down
1 change: 0 additions & 1 deletion src/mono/mono/mini/interp/mintops.def
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -824,7 +824,6 @@ OPDEF(MINT_INTRINS_GET_HASHCODE, "intrins_get_hashcode", 3, 1, 1, MintOpNoArgs)
OPDEF(MINT_INTRINS_TRY_GET_HASHCODE, "intrins_try_get_hashcode", 3, 1, 1, MintOpNoArgs)
OPDEF(MINT_INTRINS_GET_TYPE, "intrins_get_type", 3, 1, 1, MintOpNoArgs)
OPDEF(MINT_INTRINS_SPAN_CTOR, "intrins_span_ctor", 4, 1, 2, MintOpNoArgs)
OPDEF(MINT_INTRINS_UNSAFE_BYTE_OFFSET, "intrins_unsafe_byte_offset", 4, 1, 2, MintOpNoArgs)
OPDEF(MINT_INTRINS_RUNTIMEHELPERS_OBJECT_HAS_COMPONENT_SIZE, "intrins_runtimehelpers_object_has_component_size", 3, 1, 1, MintOpNoArgs)
OPDEF(MINT_INTRINS_CLEAR_WITH_REFERENCES, "intrin_clear_with_references", 3, 0, 2, MintOpNoArgs)
OPDEF(MINT_INTRINS_MARVIN_BLOCK, "intrins_marvin_block", 3, 0, 2, MintOpNoArgs)
Expand Down
45 changes: 44 additions & 1 deletion src/mono/mono/mini/interp/transform.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -2119,7 +2119,17 @@ interp_handle_intrinsics (TransformData *td, MonoMethod *target_method, MonoClas
} else if (!strcmp (tm, "AreSame")) {
*op = MINT_CEQ_P;
} else if (!strcmp (tm, "ByteOffset")) {
*op = MINT_INTRINS_UNSAFE_BYTE_OFFSET;
#if SIZEOF_VOID_P == 4
interp_add_ins (td, MINT_SUB_I4);
#else
interp_add_ins (td, MINT_SUB_I8);
#endif
td->sp -= 2;
interp_ins_set_sregs2 (td->last_ins, td->sp [1].local, td->sp [0].local);
push_simple_type (td, STACK_TYPE_I);

@kg kg Mar 16, 2023

Copy link
Copy Markdown
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

The original interp opcode looks like it was storing the result of a signed pointer subtraction into an unsigned int (mono_u), but I assume this will behave correctly as-is?

interp_ins_set_dreg (td->last_ins, td->sp [-1].local);
td->ip += 5;
return TRUE;
} else if (!strcmp (tm, "Unbox")) {
MonoGenericContext *ctx = mono_method_get_context (target_method);
g_assert (ctx);
Expand Down Expand Up @@ -9873,6 +9883,39 @@ interp_super_instructions (TransformData *td)
dump_interp_inst (new_inst);
}
}
} else if (opcode == MINT_DIV_UN_I4 || opcode == MINT_DIV_UN_I8) {
// ldc + div.un -> shr.imm
int sreg_imm = ins->sregs [1];
InterpInst *def = td->locals [sreg_imm].def;
if (def != NULL && td->local_ref_count [sreg_imm] == 1) {
int power2 = -1;
if (MINT_IS_LDC_I4 (def->opcode)) {
guint32 ct = interp_get_const_from_ldc_i4 (def);
power2 = mono_is_power_of_two ((guint32)ct);
} else if (MINT_IS_LDC_I8 (def->opcode)) {
guint64 ct = interp_get_const_from_ldc_i8 (def);
if (ct < G_MAXUINT32)
power2 = mono_is_power_of_two ((guint32)ct);
}
if (power2 > 0) {
InterpInst *new_inst;
if (opcode == MINT_DIV_UN_I4)
new_inst = interp_insert_ins (td, ins, MINT_SHR_UN_I4_IMM);
else
new_inst = interp_insert_ins (td, ins, MINT_SHR_UN_I8_IMM);
new_inst->dreg = ins->dreg;
new_inst->sregs [0] = ins->sregs [0];
new_inst->data [0] = power2;

interp_clear_ins (def);
interp_clear_ins (ins);
local_ref_count [sreg_imm]--;

@kotlarmilos kotlarmilos Mar 16, 2023

Copy link
Copy Markdown
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Probably mono_interp_stats.super_instructions++; is missing

@BrzVlad BrzVlad Mar 16, 2023

Copy link
Copy Markdown
Member Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Some of these stats are not that useful anymore, I will probably get rid of them in the future. Also this is more of a peephole optimization. This pass will probably end up being rebranded.

if (td->verbose_level) {
g_print ("lower div.un: ");
dump_interp_inst (new_inst);
}
}
}
} else if (MINT_IS_LDIND_INT (opcode)) {
int sreg_base = ins->sregs [0];
InterpInst *def = td->locals [sreg_base].def;
Expand Down
7 changes: 0 additions & 7 deletions src/mono/wasm/runtime/jiterpreter-trace-generator.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -613,13 +613,6 @@ export function generate_wasm_body (
builder.callImport("ldtsflda");
break;
}
case MintOpcode.MINT_INTRINS_UNSAFE_BYTE_OFFSET:
builder.local("pLocals");
append_ldloc(builder, getArgU16(ip, 3), WasmOpcode.i32_load);
append_ldloc(builder, getArgU16(ip, 2), WasmOpcode.i32_load);
builder.appendU8(WasmOpcode.i32_sub);
append_stloc_tail(builder, getArgU16(ip, 1), WasmOpcode.i32_store);
break;
case MintOpcode.MINT_INTRINS_GET_TYPE:
builder.block();
// dest, src
Expand Down