Skip to content

[llvmonly] Avoid marking the rgctx/vtable variable indirect, its not needed. #33955

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
vargaz merged 1 commit into from
Mar 30, 2020
Merged

[llvmonly] Avoid marking the rgctx/vtable variable indirect, its not needed. #33955

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
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
34 changes: 28 additions & 6 deletions src/mono/mono/mini/method-to-ir.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1367,15 +1367,27 @@ mono_create_rgctx_var (MonoCompile *cfg)
if (!cfg->rgctx_var) {
cfg->rgctx_var = mono_compile_create_var (cfg, mono_get_int_type (), OP_LOCAL);
/* force the var to be stack allocated */
cfg->rgctx_var->flags |= MONO_INST_VOLATILE;
if (!cfg->llvm_only)
cfg->rgctx_var->flags |= MONO_INST_VOLATILE;
}
}

static MonoInst *
mono_get_mrgctx_var (MonoCompile *cfg)
{
g_assert (cfg->gshared);

mono_create_rgctx_var (cfg);

return cfg->rgctx_var;
}

static MonoInst *
mono_get_vtable_var (MonoCompile *cfg)
{
g_assert (cfg->gshared);

/* The mrgctx and the vtable are stored in the same var */
mono_create_rgctx_var (cfg);

return cfg->rgctx_var;
Expand Down Expand Up @@ -2467,17 +2479,27 @@ emit_get_rgctx (MonoCompile *cfg, int context_used)
g_assert (method->is_inflated && mono_method_get_context (method)->method_inst);
}

mrgctx_loc = mono_get_vtable_var (cfg);
EMIT_NEW_TEMPLOAD (cfg, mrgctx_var, mrgctx_loc->inst_c0);

if (cfg->llvm_only) {
mrgctx_var = mono_get_mrgctx_var (cfg);
} else {
/* Volatile */
mrgctx_loc = mono_get_mrgctx_var (cfg);
g_assert (mrgctx_loc->flags & MONO_INST_VOLATILE);
EMIT_NEW_TEMPLOAD (cfg, mrgctx_var, mrgctx_loc->inst_c0);
}
return mrgctx_var;
} else if (method->flags & METHOD_ATTRIBUTE_STATIC || m_class_is_valuetype (method->klass)) {
MonoInst *vtable_loc, *vtable_var;

g_assert (!this_ins);

vtable_loc = mono_get_vtable_var (cfg);
EMIT_NEW_TEMPLOAD (cfg, vtable_var, vtable_loc->inst_c0);
if (cfg->llvm_only) {
vtable_var = mono_get_vtable_var (cfg);
} else {
vtable_loc = mono_get_vtable_var (cfg);
g_assert (vtable_loc->flags & MONO_INST_VOLATILE);
EMIT_NEW_TEMPLOAD (cfg, vtable_var, vtable_loc->inst_c0);
}

if (method->is_inflated && mono_method_get_context (method)->method_inst) {
MonoInst *mrgctx_var = vtable_var;
Expand Down
38 changes: 24 additions & 14 deletions src/mono/mono/mini/mini-llvm.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -3447,7 +3447,7 @@ emit_entry_bb (EmitContext *ctx, LLVMBuilderRef builder)
#ifdef TARGET_WASM
// For GC stack scanning to work, have to spill all reference variables to the stack
// Some ref variables have type intptr
if (ctx->has_safepoints && (MONO_TYPE_IS_REFERENCE (var->inst_vtype) || var->inst_vtype->type == MONO_TYPE_I))
if (ctx->has_safepoints && (MONO_TYPE_IS_REFERENCE (var->inst_vtype) || var->inst_vtype->type == MONO_TYPE_I) && var != ctx->cfg->rgctx_var)
var->flags |= MONO_INST_INDIRECT;
#endif

Expand Down Expand Up @@ -3601,7 +3601,7 @@ emit_entry_bb (EmitContext *ctx, LLVMBuilderRef builder)
if (!mini_type_is_vtype (sig->params [i]))
emit_volatile_store (ctx, cfg->args [i + sig->hasthis]->dreg);

if (sig->hasthis && !cfg->rgctx_var && cfg->gshared) {
if (sig->hasthis && !cfg->rgctx_var && cfg->gshared && !cfg->llvm_only) {
LLVMValueRef this_alloc;

/*
Expand All @@ -3618,17 +3618,23 @@ emit_entry_bb (EmitContext *ctx, LLVMBuilderRef builder)
}

if (cfg->rgctx_var) {
LLVMValueRef rgctx_alloc, store;
if (!(cfg->rgctx_var->flags & MONO_INST_VOLATILE)) {
/* FIXME: This could be volatile even in llvmonly mode if used inside a clause etc. */
g_assert (!ctx->addresses [cfg->rgctx_var->dreg]);
ctx->values [cfg->rgctx_var->dreg] = ctx->rgctx_arg;
} else {
LLVMValueRef rgctx_alloc, store;

/*
* We handle the rgctx arg similarly to the this pointer.
*/
g_assert (ctx->addresses [cfg->rgctx_var->dreg]);
rgctx_alloc = ctx->addresses [cfg->rgctx_var->dreg];
/* This volatile store will keep the alloca alive */
store = mono_llvm_build_store (builder, convert (ctx, ctx->rgctx_arg, IntPtrType ()), rgctx_alloc, TRUE, LLVM_BARRIER_NONE);
/*
* We handle the rgctx arg similarly to the this pointer.
*/
g_assert (ctx->addresses [cfg->rgctx_var->dreg]);
rgctx_alloc = ctx->addresses [cfg->rgctx_var->dreg];
/* This volatile store will keep the alloca alive */
store = mono_llvm_build_store (builder, convert (ctx, ctx->rgctx_arg, IntPtrType ()), rgctx_alloc, TRUE, LLVM_BARRIER_NONE);

set_metadata_flag (rgctx_alloc, "mono.this");
set_metadata_flag (rgctx_alloc, "mono.this");
}
}

/* Initialize the method if needed */
Expand Down Expand Up @@ -4323,9 +4329,13 @@ mono_llvm_emit_match_exception_call (EmitContext *ctx, LLVMBuilderRef builder, g
args [1] = LLVMConstInt (LLVMInt32Type (), region_start, 0);
args [2] = LLVMConstInt (LLVMInt32Type (), region_end, 0);
if (ctx->cfg->rgctx_var) {
LLVMValueRef rgctx_alloc = ctx->addresses [ctx->cfg->rgctx_var->dreg];
g_assert (rgctx_alloc);
args [3] = LLVMBuildLoad (builder, convert (ctx, rgctx_alloc, LLVMPointerType (IntPtrType (), 0)), "");
if (ctx->cfg->llvm_only) {
args [3] = convert (ctx, ctx->rgctx_arg, IntPtrType ());
} else {
LLVMValueRef rgctx_alloc = ctx->addresses [ctx->cfg->rgctx_var->dreg];
g_assert (rgctx_alloc);
args [3] = LLVMBuildLoad (builder, convert (ctx, rgctx_alloc, LLVMPointerType (IntPtrType (), 0)), "");
}
} else {
args [3] = LLVMConstInt (IntPtrType (), 0, 0);
}
Expand Down
3 changes: 2 additions & 1 deletion src/mono/mono/mini/mini.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1287,7 +1287,8 @@ typedef struct {
MonoInst *domainvar; /* a cache for the current domain */
MonoInst *got_var; /* Global Offset Table variable */
MonoInst **locals;
MonoInst *rgctx_var; /* Runtime generic context variable (for static generic methods) */
/* Variable holding the mrgctx/vtable address for gshared methods */
MonoInst *rgctx_var;
MonoInst **args;
MonoType **arg_types;
MonoMethod *current_method; /* The method currently processed by method_to_ir () */
Expand Down