1; RUN: llc < %s -mtriple=i686-- -stackrealign -O2 | FileCheck %s 2; PR28755 3 4; Check that register allocator is able to handle that 5; a-lot-of-fixed-and-reserved-registers case. We do that by 6; emmiting lea before 4 cmpxchg8b operands generators. 7 8define void @foo_alloca(ptr %a, i32 %off, i32 %n) { 9 %dummy = alloca i32, i32 %n 10 %addr = getelementptr inbounds i64, ptr %a, i32 %off 11 12 %res = cmpxchg ptr %addr, i64 0, i64 1 monotonic monotonic 13 ret void 14} 15 16; CHECK-LABEL: foo_alloca 17; CHECK: leal {{\(%e..,%e..,.*\)}}, [[REGISTER:%e.i]] 18; CHECK-NEXT: xorl %eax, %eax 19; CHECK-NEXT: xorl %edx, %edx 20; CHECK-NEXT: xorl %ecx, %ecx 21; CHECK-NEXT: movl $1, %ebx 22; CHECK-NEXT: lock cmpxchg8b ([[REGISTER]]) 23 24; If we don't use index register in the address mode - 25; check that we did not generate the lea. 26define void @foo_alloca_direct_address(ptr %addr, i32 %n) { 27 %dummy = alloca i32, i32 %n 28 29 %res = cmpxchg ptr %addr, i64 0, i64 1 monotonic monotonic 30 ret void 31} 32 33; CHECK-LABEL: foo_alloca_direct_address 34; CHECK-NOT: leal {{\(%e.*\)}}, [[REGISTER:%e.i]] 35; CHECK: lock cmpxchg8b ([[REGISTER]]) 36 37; We used to have a bug when combining: 38; - base pointer for stack frame (VLA + alignment) 39; - cmpxchg8b frameindex + index reg 40 41declare void @escape(ptr) 42 43define void @foo_alloca_index(i32 %i, i64 %val) { 44entry: 45 %Counters = alloca [19 x i64], align 32 46 %vla = alloca i32, i32 %i 47 call void @escape(ptr %vla) 48 br label %body 49 50body: 51 %p = getelementptr inbounds [19 x i64], ptr %Counters, i32 0, i32 %i 52 %t2 = cmpxchg volatile ptr %p, i64 %val, i64 %val seq_cst seq_cst 53 %t3 = extractvalue { i64, i1 } %t2, 0 54 %cmp.i = icmp eq i64 %val, %t3 55 br i1 %cmp.i, label %done, label %body 56 57done: 58 ret void 59} 60 61; Check that we add a LEA 62; CHECK-LABEL: foo_alloca_index: 63; CHECK: leal {{[0-9]*\(%e..,%e..,8\), %e..}} 64; CHECK: lock cmpxchg8b ({{%e..}}) 65 66 67 68; We used to have a bug when combining: 69; - base pointer for stack frame (VLA + alignment) 70; - cmpxchg8b global + index reg 71 72@Counters = external dso_local global [19 x i64] 73 74define void @foo_alloca_index_global(i32 %i, i64 %val) { 75entry: 76 %aligner = alloca i32, align 32 77 call void @escape(ptr %aligner) 78 %vla = alloca i32, i32 %i 79 call void @escape(ptr %vla) 80 br label %body 81 82body: 83 %p = getelementptr inbounds [19 x i64], ptr @Counters, i32 0, i32 %i 84 %t2 = cmpxchg volatile ptr %p, i64 %val, i64 %val seq_cst seq_cst 85 %t3 = extractvalue { i64, i1 } %t2, 0 86 %cmp.i = icmp eq i64 %val, %t3 87 br i1 %cmp.i, label %done, label %body 88 89done: 90 ret void 91} 92 93; Check that we add a LEA 94; CHECK-LABEL: foo_alloca_index_global: 95; CHECK: leal {{Counters\(,%e..,8\), %e..}} 96; CHECK: lock cmpxchg8b ({{%e..}}) 97