1 ; This test is attempting to detect when we request forced re-alignment of the 2 ; stack to an alignment greater than would be available due to the ABI. We 3 ; arbitrarily force alignment up to 32-bytes for i386 hoping that this will 4 ; exceed any ABI provisions. 5 ; 6 ; RUN: llc < %s -mcpu=generic -stackrealign -stack-alignment=32 | FileCheck %s 7 8 target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:32:32-n8:16:32-S128" 9 target triple = "i386-unknown-linux-gnu" 10 11 define i32 @f(i8* %p) nounwind { 12 entry: 13 %0 = load i8, i8* %p 14 %conv = sext i8 %0 to i32 15 ret i32 %conv 16 } 17 18 define i64 @g(i32 %i) nounwind { 19 ; CHECK-LABEL: g: 20 ; CHECK: pushl %ebp 21 ; CHECK-NEXT: movl %esp, %ebp 22 ; CHECK-NEXT: pushl 23 ; CHECK-NEXT: pushl 24 ; CHECK-NEXT: andl $-32, %esp 25 ; CHECK-NEXT: subl $32, %esp 26 ; 27 ; Now setup the base pointer (%esi). 28 ; CHECK-NEXT: movl %esp, %esi 29 ; CHECK-NOT: {{[^ ,]*}}, %esp 30 ; 31 ; The next adjustment of the stack is due to the alloca. 32 ; CHECK: movl %{{...}}, %esp 33 ; CHECK-NOT: {{[^ ,]*}}, %esp 34 ; 35 ; Next we set up the memset call. 36 ; CHECK: subl $20, %esp 37 ; CHECK-NOT: {{[^ ,]*}}, %esp 38 ; CHECK: pushl 39 ; CHECK: pushl 40 ; CHECK: pushl 41 ; CHECK: calll memset 42 ; 43 ; Deallocating 32 bytes of outgoing call frame for memset and 44 ; allocating 28 bytes for calling f yields a 4-byte adjustment: 45 ; CHECK-NEXT: addl $4, %esp 46 ; CHECK-NOT: {{[^ ,]*}}, %esp 47 ; 48 ; And move on to call 'f', and then restore the stack. 49 ; CHECK: pushl 50 ; CHECK-NOT: {{[^ ,]*}}, %esp 51 ; CHECK: calll f 52 ; CHECK-NEXT: addl $32, %esp 53 ; CHECK-NOT: {{[^ ,]*}}, %esp 54 ; 55 ; Restore %esp from %ebp (frame pointer) and subtract the size of 56 ; zone with callee-saved registers to pop them. 57 ; This is the state prior to stack realignment and the allocation of VLAs. 58 ; CHECK-NOT: popl 59 ; CHECK: leal -8(%ebp), %esp 60 ; CHECK-NEXT: popl 61 ; CHECK-NEXT: popl 62 ; CHECK-NEXT: popl %ebp 63 ; CHECK-NEXT: ret 64 65 entry: 66 br label %if.then 67 68 if.then: 69 %0 = alloca i8, i32 %i 70 call void @llvm.memset.p0i8.i32(i8* %0, i8 0, i32 %i, i32 1, i1 false) 71 %call = call i32 @f(i8* %0) 72 %conv = sext i32 %call to i64 73 ret i64 %conv 74 } 75 76 declare void @llvm.memset.p0i8.i32(i8*, i8, i32, i32, i1) nounwind 77
