Use byte-aligned LLVM loads and stores for unaligned mini IR loads an…

…d stores. (mono/mono#18296)

Should fix mono/mono#18221.

Commit migrated from mono/mono@9719635

src/mono/mono/mini/mini-llvm.c

@@ -5761,6 +5761,7 @@ process_bb (EmitContext *ctx, MonoBasicBlock *bb)
 			gboolean sext = FALSE, zext = FALSE;
 			gboolean is_faulting = (ins->flags & MONO_INST_FAULT) != 0;
 			gboolean is_volatile = (ins->flags & MONO_INST_VOLATILE) != 0;
+			gboolean is_unaligned = (ins->flags & MONO_INST_UNALIGNED) != 0;
 
 			t = load_store_to_llvm_type (ins->opcode, &size, &sext, &zext);
 
@@ -5793,7 +5794,10 @@ process_bb (EmitContext *ctx, MonoBasicBlock *bb)
 
 			addr = convert (ctx, addr, LLVMPointerType (t, 0));
 
-			values [ins->dreg] = emit_load (ctx, bb, &builder, size, addr, base, dname, is_faulting, is_volatile, LLVM_BARRIER_NONE);
+			if (is_unaligned)
+				values [ins->dreg] = mono_llvm_build_aligned_load (builder, addr, dname, is_volatile, 1);
+			else
+				values [ins->dreg] = emit_load (ctx, bb, &builder, size, addr, base, dname, is_faulting, is_volatile, LLVM_BARRIER_NONE);
 
 			if (!(is_faulting || is_volatile) && (ins->flags & MONO_INST_INVARIANT_LOAD)) {
 				/*
@@ -5811,7 +5815,7 @@ process_bb (EmitContext *ctx, MonoBasicBlock *bb)
 				values [ins->dreg] = LLVMBuildFPExt (builder, values [ins->dreg], LLVMDoubleType (), dname);
 			break;
 		}
-				
+
 		case OP_STOREI1_MEMBASE_REG:
 		case OP_STOREI2_MEMBASE_REG:
 		case OP_STOREI4_MEMBASE_REG:
@@ -5825,6 +5829,7 @@ process_bb (EmitContext *ctx, MonoBasicBlock *bb)
 			gboolean sext = FALSE, zext = FALSE;
 			gboolean is_faulting = (ins->flags & MONO_INST_FAULT) != 0;
 			gboolean is_volatile = (ins->flags & MONO_INST_VOLATILE) != 0;
+			gboolean is_unaligned = (ins->flags & MONO_INST_UNALIGNED) != 0;
 
 			if (!values [ins->inst_destbasereg]) {
 				set_failure (ctx, "inst_destbasereg");
@@ -5842,13 +5847,19 @@ process_bb (EmitContext *ctx, MonoBasicBlock *bb)
 				index = LLVMConstInt (LLVMInt32Type (), ins->inst_offset, FALSE);
 				addr = LLVMBuildGEP (builder, convert (ctx, base, LLVMPointerType (LLVMInt8Type (), 0)), &index, 1, "");
 			} else {
-				index = LLVMConstInt (LLVMInt32Type (), ins->inst_offset / size, FALSE);				
+				index = LLVMConstInt (LLVMInt32Type (), ins->inst_offset / size, FALSE);
 				addr = LLVMBuildGEP (builder, convert (ctx, base, LLVMPointerType (t, 0)), &index, 1, "");
 			}
 			if (is_volatile && LLVMGetInstructionOpcode (base) == LLVMAlloca && !(ins->flags & MONO_INST_VOLATILE))
 				/* Storing to an alloca cannot fail */
 				is_volatile = FALSE;
-			emit_store (ctx, bb, &builder, size, convert (ctx, values [ins->sreg1], t), convert (ctx, addr, LLVMPointerType (t, 0)), base, is_faulting, is_volatile);
+			LLVMValueRef srcval = convert (ctx, values [ins->sreg1], t);
+			LLVMValueRef ptrdst = convert (ctx, addr, LLVMPointerType (t, 0));
+
+			if (is_unaligned)
+				mono_llvm_build_aligned_store (builder, srcval, ptrdst, is_volatile, 1);
+			else
+				emit_store (ctx, bb, &builder, size, srcval, ptrdst, base, is_faulting, is_volatile);
 			break;
 		}
 
@@ -5863,6 +5874,7 @@ process_bb (EmitContext *ctx, MonoBasicBlock *bb)
 			gboolean sext = FALSE, zext = FALSE;
 			gboolean is_faulting = (ins->flags & MONO_INST_FAULT) != 0;
 			gboolean is_volatile = (ins->flags & MONO_INST_VOLATILE) != 0;
+			gboolean is_unaligned = (ins->flags & MONO_INST_UNALIGNED) != 0;
 
 			t = load_store_to_llvm_type (ins->opcode, &size, &sext, &zext);
 
@@ -5875,10 +5887,15 @@ process_bb (EmitContext *ctx, MonoBasicBlock *bb)
 				index = LLVMConstInt (LLVMInt32Type (), ins->inst_offset, FALSE);
 				addr = LLVMBuildGEP (builder, convert (ctx, base, LLVMPointerType (LLVMInt8Type (), 0)), &index, 1, "");
 			} else {
-				index = LLVMConstInt (LLVMInt32Type (), ins->inst_offset / size, FALSE);				
+				index = LLVMConstInt (LLVMInt32Type (), ins->inst_offset / size, FALSE);
 				addr = LLVMBuildGEP (builder, convert (ctx, base, LLVMPointerType (t, 0)), &index, 1, "");
 			}
-			emit_store (ctx, bb, &builder, size, convert (ctx, LLVMConstInt (IntPtrType (), ins->inst_imm, FALSE), t), convert (ctx, addr, LLVMPointerType (t, 0)), base, is_faulting, is_volatile);
+			LLVMValueRef srcval = convert (ctx, LLVMConstInt (IntPtrType (), ins->inst_imm, FALSE), t);
+			LLVMValueRef ptrdst = convert (ctx, addr, LLVMPointerType (t, 0));
+			if (is_unaligned)
+				mono_llvm_build_aligned_store (builder, srcval, ptrdst, is_volatile, 1);
+			else
+				emit_store (ctx, bb, &builder, size, srcval, ptrdst, base, is_faulting, is_volatile);
 			break;
 		}