; RUN: llc < %s -mtriple=i686-- -stackrealign -O2 | FileCheck %s ; PR28755 ; Check that register allocator is able to handle that ; a-lot-of-fixed-and-reserved-registers case. We do that by ; emmiting lea before 4 cmpxchg8b operands generators. define void @foo_alloca(i64* %a, i32 %off, i32 %n) { %dummy = alloca i32, i32 %n %addr = getelementptr inbounds i64, i64* %a, i32 %off %res = cmpxchg i64* %addr, i64 0, i64 1 monotonic monotonic ret void } ; CHECK-LABEL: foo_alloca ; CHECK: leal {{\(%e..,%e..,.*\)}}, [[REGISTER:%e.i]] ; CHECK-NEXT: xorl %eax, %eax ; CHECK-NEXT: xorl %edx, %edx ; CHECK-NEXT: xorl %ecx, %ecx ; CHECK-NEXT: movl $1, %ebx ; CHECK-NEXT: lock cmpxchg8b ([[REGISTER]]) ; If we don't use index register in the address mode - ; check that we did not generate the lea. define void @foo_alloca_direct_address(i64* %addr, i32 %n) { %dummy = alloca i32, i32 %n %res = cmpxchg i64* %addr, i64 0, i64 1 monotonic monotonic ret void } ; CHECK-LABEL: foo_alloca_direct_address ; CHECK-NOT: leal {{\(%e.*\)}}, [[REGISTER:%e.i]] ; CHECK: lock cmpxchg8b ([[REGISTER]]) ; We used to have a bug when combining: ; - base pointer for stack frame (VLA + alignment) ; - cmpxchg8b frameindex + index reg declare void @escape(i32*) define void @foo_alloca_index(i32 %i, i64 %val) { entry: %Counters = alloca [19 x i64], align 32 %vla = alloca i32, i32 %i call void @escape(i32* %vla) br label %body body: %p = getelementptr inbounds [19 x i64], [19 x i64]* %Counters, i32 0, i32 %i %t2 = cmpxchg volatile i64* %p, i64 %val, i64 %val seq_cst seq_cst %t3 = extractvalue { i64, i1 } %t2, 0 %cmp.i = icmp eq i64 %val, %t3 br i1 %cmp.i, label %done, label %body done: ret void } ; Check that we add a LEA ; CHECK-LABEL: foo_alloca_index: ; CHECK: leal {{[0-9]*\(%e..,%e..,8\), %e..}} ; CHECK: lock cmpxchg8b ({{%e..}}) ; We used to have a bug when combining: ; - base pointer for stack frame (VLA + alignment) ; - cmpxchg8b global + index reg @Counters = external dso_local global [19 x i64] define void @foo_alloca_index_global(i32 %i, i64 %val) { entry: %aligner = alloca i32, align 32 call void @escape(i32* %aligner) %vla = alloca i32, i32 %i call void @escape(i32* %vla) br label %body body: %p = getelementptr inbounds [19 x i64], [19 x i64]* @Counters, i32 0, i32 %i %t2 = cmpxchg volatile i64* %p, i64 %val, i64 %val seq_cst seq_cst %t3 = extractvalue { i64, i1 } %t2, 0 %cmp.i = icmp eq i64 %val, %t3 br i1 %cmp.i, label %done, label %body done: ret void } ; Check that we add a LEA ; CHECK-LABEL: foo_alloca_index_global: ; CHECK: leal {{Counters\(,%e..,8\), %e..}} ; CHECK: lock cmpxchg8b ({{%e..}})