llvm/test/CodeGen/ARM/ifcvt10.ll
Evan Cheng 3ef1c8759a Teach if-converter to be more careful with predicating instructions that would
take multiple cycles to decode.
For the current if-converter clients (actually only ARM), the instructions that
are predicated on false are not nops. They would still take machine cycles to
decode. Micro-coded instructions such as LDM / STM can potentially take multiple
cycles to decode. If-converter should take treat them as non-micro-coded
simple instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@113570 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-10 01:29:16 +00:00

31 lines
1.0 KiB
LLVM

; RUN: llc < %s -march=arm -mcpu=cortex-a8 | FileCheck %s
; rdar://8402126
; Make sure if-converter is not predicating vldmia and ldmia. These are
; micro-coded and would have long issue latency even if predicated on
; false predicate.
%0 = type { float, float, float, float }
%pln = type { %vec, float }
%vec = type { [4 x float] }
define arm_aapcs_vfpcc float @aaa(%vec* nocapture %ustart, %vec* nocapture %udir, %vec* nocapture %vstart, %vec* nocapture %vdir, %vec* %upoint, %vec* %vpoint) {
; CHECK: aaa:
; CHECK: vldr.32
; CHECK-NOT: vldrne
; CHECK-NOT: vldmiane
; CHECK-NOT: ldmiane
; CHECK: vldmia sp!
; CHECK: ldmia sp!
entry:
br i1 undef, label %bb81, label %bb48
bb48: ; preds = %entry
%0 = call arm_aapcs_vfpcc %0 @bbb(%pln* undef, %vec* %vstart, %vec* undef) nounwind ; <%0> [#uses=0]
ret float 0.000000e+00
bb81: ; preds = %entry
ret float 0.000000e+00
}
declare arm_aapcs_vfpcc %0 @bbb(%pln* nocapture, %vec* nocapture, %vec* nocapture) nounwind