[BreakFalseDeps] ignore function with minsize attribute

This came up in the x86-specific:
https://bugs.llvm.org/show_bug.cgi?id=43239
...but it is a general problem for the BreakFalseDeps pass.
Dependencies may be broken by adding some other instruction,
so that should be avoided if the overall goal is to minimize size.

Differential Revision: https://reviews.llvm.org/D67363

llvm-svn: 372628

1 files changed, 5 insertions, 1 deletions

diff --git a/llvm/test/CodeGen/ARM/a15-partial-update.ll b/llvm/test/CodeGen/ARM/a15-partial-update.ll
index c20aaa2fa5d..a3971d6a034 100644
--- a/llvm/test/CodeGen/ARM/a15-partial-update.ll
+++ b/llvm/test/CodeGen/ARM/a15-partial-update.ll
@@ -56,6 +56,11 @@ ret:
   ret void
 }
 
+; If minimizing size, that overrides perf, so no extra vmov.f64 here.
+
+; TODO: This (and above) could use a splat load to remove the false
+;       dependence with no extra instruction.
+
 define void @t2_minsize(<4 x i8> *%in, <4 x i8> *%out, i32 %n) minsize {
 ; CHECK-LABEL: t2_minsize:
 ; CHECK:       @ %bb.0: @ %entry
@@ -63,7 +68,6 @@ define void @t2_minsize(<4 x i8> *%in, <4 x i8> *%out, i32 %n) minsize {
 ; CHECK-NEXT:    add r1, r1, #4
 ; CHECK-NEXT:  .LBB2_1: @ %loop
 ; CHECK-NEXT:    @ =>This Inner Loop Header: Depth=1
-; CHECK-NEXT:    vmov.f64 d16, #5.000000e-01
 ; CHECK-NEXT:    vld1.32 {d16[0]}, [r0:32]
 ; CHECK-NEXT:    vmovl.u8 q8, d16
 ; CHECK-NEXT:    vuzp.8 d16, d18