llvm-project/llvm/test/CodeGen/PowerPC/pr13641.ll

; RUN: llc < %s | FileCheck %s
target datalayout = "E-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v128:128:128-n32:64"
target triple = "powerpc64-unknown-linux-gnu"

define void @foo() nounwind {
  ret void
}

; CHECK: blr
; CHECK-NEXT: .long 0
; CHECK-NEXT: .quad 0
Emit word of zeroes after the last instruction as a start of the mandatory traceback table on PowerPC64. This helps gdb handle exceptions. The other mandatory fields are ignored by gdb and harder to implement so just add there a FIXME. Patch by Bill Schmidt. PR13641. llvm-svn: 162778 2012-08-29 03:06:55 +08:00			`; RUN: llc < %s \| FileCheck %s`
			`target datalayout = "E-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v128:128:128-n32:64"`
			`target triple = "powerpc64-unknown-linux-gnu"`

			`define void @foo() nounwind {`
			`ret void`
			`}`

			`; CHECK: blr`
			`; CHECK-NEXT: .long 0`
Reserve space for the mandatory traceback fields on PPC64. We need to reserve space for the mandatory traceback fields, though leaving them as zero is appropriate for now. Although the ABI calls for these fields to be filled in fully, no compiler on Linux currently does this, and GDB does not read these fields. GDB uses the first word of zeroes during exception handling to find the end of the function and the size field, allowing it to compute the beginning of the function. DWARF information is used for everything else. We need the extra 8 bytes of pad so the size field is found in the right place. As a comparison, GCC fills in a few of the fields -- language, number of saved registers -- but ignores the rest. IBM's proprietary OSes do make use of the full traceback table facility. Patch by Bill Schmidt. llvm-svn: 162854 2012-08-30 04:22:24 +08:00			`; CHECK-NEXT: .quad 0`