llvm/test/Bitcode/callbr.ll
Craig Topper e3696113b6 Implementation of asm-goto support in LLVM
This patch accompanies the RFC posted here:
http://lists.llvm.org/pipermail/llvm-dev/2018-October/127239.html

This patch adds a new CallBr IR instruction to support asm-goto
inline assembly like gcc as used by the linux kernel. This
instruction is both a call instruction and a terminator
instruction with multiple successors. Only inline assembly
usage is supported today.

This also adds a new INLINEASM_BR opcode to SelectionDAG and
MachineIR to represent an INLINEASM block that is also
considered a terminator instruction.

There will likely be more bug fixes and optimizations to follow
this, but we felt it had reached a point where we would like to
switch to an incremental development model.

Patch by Craig Topper, Alexander Ivchenko, Mikhail Dvoretckii

Differential Revision: https://reviews.llvm.org/D53765

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353563 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-08 20:48:56 +00:00

15 lines
428 B
LLVM

; RUN: llvm-dis < %s.bc | FileCheck %s
; callbr.ll.bc was generated by passing this file to llvm-as.
define i32 @test_asm_goto(i32 %x){
entry:
; CHECK: callbr void asm "", "r,X"(i32 %x, i8* blockaddress(@test_asm_goto, %fail))
; CHECK-NEXT: to label %normal [label %fail]
callbr void asm "", "r,X"(i32 %x, i8* blockaddress(@test_asm_goto, %fail)) to label %normal [label %fail]
normal:
ret i32 1
fail:
ret i32 0
}