llvm-6502/test/CodeGen/X86/disable-tail-calls.ll
Akira Hatanaka 0e3246a86f Remove DisableTailCalls from TargetOptions and the code in resetTargetOptions
that was resetting it.

Remove the uses of DisableTailCalls in subclasses of TargetLowering and use
the value of function attribute "disable-tail-calls" instead. Also,
unconditionally add pass TailCallElim to the pipeline and check the function
attribute at the start of runOnFunction to disable the pass on a per-function
basis. 
 
This is part of the work to remove TargetMachine::resetTargetOptions, and since
DisableTailCalls was the last non-fast-math option that was being reset in that
function, we should be able to remove the function entirely after the work to
propagate IR-level fast-math flags to DAG nodes is completed.

Out-of-tree users should remove the uses of DisableTailCalls and make changes
to attach attribute "disable-tail-calls"="true" or "false" to the functions in
the IR.

rdar://problem/13752163

Differential Revision: http://reviews.llvm.org/D10099


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239427 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-09 19:07:19 +00:00

41 lines
1.1 KiB
LLVM

; RUN: llc < %s -march x86-64 | FileCheck %s --check-prefix=NO-OPTION
; RUN: llc < %s -march x86-64 -disable-tail-calls | FileCheck %s --check-prefix=DISABLE-TRUE
; RUN: llc < %s -march x86-64 -disable-tail-calls=false | FileCheck %s --check-prefix=DISABLE-FALSE
; Check that command line option "-disable-tail-calls" overrides function
; attribute "disable-tail-calls".
; NO-OPTION-LABEL: {{\_?}}func_attr
; NO-OPTION: callq {{\_?}}callee
; DISABLE-FALSE-LABEL: {{\_?}}func_attr
; DISABLE-FALSE: jmp {{\_?}}callee
; DISABLE-TRUE-LABEL: {{\_?}}func_attr
; DISABLE-TRUE: callq {{\_?}}callee
define i32 @func_attr(i32 %a) #0 {
entry:
%call = tail call i32 @callee(i32 %a)
ret i32 %call
}
; NO-OPTION-LABEL: {{\_?}}func_noattr
; NO-OPTION: jmp {{\_?}}callee
; DISABLE-FALSE-LABEL: {{\_?}}func_noattr
; DISABLE-FALSE: jmp {{\_?}}callee
; DISABLE-TRUE-LABEL: {{\_?}}func_noattr
; DISABLE-TRUE: callq {{\_?}}callee
define i32 @func_noattr(i32 %a) {
entry:
%call = tail call i32 @callee(i32 %a)
ret i32 %call
}
declare i32 @callee(i32)
attributes #0 = { "disable-tail-calls"="true" }