[mono][jit] Avoid doing copy propagation on ldaddr for gsharedvt vari…

…ables. (#87713) Ldaddr requires the emission of dummy uses for gsharedvt_info_var/gsharedvt_locals_var and the copy wouldn't have these, leading to register allocation problems. Fixes #87551.
dotnet · Jun 21, 2023 · fc75f7e · fc75f7e
1 parent 57cfd06
commit fc75f7e
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Showing 3 changed files with 8 additions and 3 deletions.
diff --git a/src/mono/mono/mini/local-propagation.c b/src/mono/mono/mini/local-propagation.c
@@ -741,7 +741,8 @@ mono_local_cprop (MonoCompile *cfg)
 				} else if (srcindex == 0 && ins->opcode == OP_COMPARE && defs [ins->sreg1]->opcode == OP_PCONST && defs [ins->sreg2] && defs [ins->sreg2]->opcode == OP_PCONST) {
 					/* typeof(T) == typeof(..) */
 					mono_constant_fold_ins (cfg, ins, defs [ins->sreg1], defs [ins->sreg2], TRUE);
-				} else if (ins->opcode == OP_MOVE && def->opcode == OP_LDADDR) {
+				} else if (ins->opcode == OP_MOVE && def->opcode == OP_LDADDR && !(G_UNLIKELY (cfg->gsharedvt) && mini_is_gsharedvt_variable_klass (def->klass))) {
+					/* Can't copyprop ldaddr for gsharedvt vars because the copy is missing the uses added by handle_gsharedvt_ldaddr () */
 					ins->opcode = OP_LDADDR;
 					ins->sreg1 = -1;
 					ins->inst_p0 = def->inst_p0;

diff --git a/src/mono/mono/mini/method-to-ir.c b/src/mono/mono/mini/method-to-ir.c
@@ -6722,7 +6722,10 @@ mono_method_to_ir (MonoCompile *cfg, MonoMethod *method, MonoBasicBlock *start_b
 		cfg->gsharedvt_info = info;
 
 		var = mono_compile_create_var (cfg, mono_get_int_type (), OP_LOCAL);
-		/* prevent it from being register allocated */
+		/*
+		 * Decomposing ldaddr creates uses for this and gsharedvt_locals_var, so
+		 * when we emit an ldaddr, we emit dummy uses for these in handle_gsharedvt_ldaddr ().
+		 */
 		//var->flags |= MONO_INST_VOLATILE;
 		cfg->gsharedvt_info_var = var;
 

diff --git a/src/mono/mono/mini/mini-generic-sharing.c b/src/mono/mono/mini/mini-generic-sharing.c
@@ -2753,7 +2753,7 @@ mono_rgctx_info_type_to_str (MonoRgctxInfoType type)
 	case MONO_RGCTX_INFO_REFLECTION_TYPE: return "REFLECTION_TYPE";
 	case MONO_RGCTX_INFO_METHOD: return "METHOD";
 	case MONO_RGCTX_INFO_METHOD_FTNDESC: return "METHOD_FTNDESC";
-	case MONO_RGCTX_INFO_METHOD_GSHAREDVT_INFO: return "GSHAREDVT_INFO";
+	case MONO_RGCTX_INFO_METHOD_GSHAREDVT_INFO: return "METHOD_GSHAREDVT_INFO";
 	case MONO_RGCTX_INFO_GENERIC_METHOD_CODE: return "GENERIC_METHOD_CODE";
 	case MONO_RGCTX_INFO_GSHAREDVT_OUT_WRAPPER: return "GSHAREDVT_OUT_WRAPPER";
 	case MONO_RGCTX_INFO_INTERP_METHOD: return "INTERP_METHOD";
@@ -2782,6 +2782,7 @@ mono_rgctx_info_type_to_str (MonoRgctxInfoType type)
 	case MONO_RGCTX_INFO_VIRT_METHOD_CODE: return "VIRT_METHOD_CODE";
 	case MONO_RGCTX_INFO_VIRT_METHOD_BOX_TYPE: return "VIRT_METHOD_BOX_TYPE";
 	case MONO_RGCTX_INFO_DELEGATE_TRAMP_INFO: return "DELEGATE_TRAMP_INFO";
+	case MONO_RGCTX_INFO_GSHAREDVT_CONSTRAINED_CALL_INFO: return "GSHAREDVT_CONSTRAINED_CALL_INFO";
 	default:
 		return "<UNKNOWN RGCTX INFO TYPE>";
 	}