llvm-6502/test/CodeGen/Hexagon/BranchPredict.ll
Jyotsna Verma 21e6ea54ff Hexagon: Test case to check if branch probabilities are properly reflected in
the jump instructions in the form of taken/not-taken hint.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181799 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-14 15:50:49 +00:00

80 lines
2.8 KiB
LLVM

; RUN: llc -march=hexagon -mcpu=hexagonv4 < %s | FileCheck %s
; Check if the branch probabilities are reflected in the instructions:
; The basic block placement pass should place the more probable successor
; block as the fall-through block. The unconditional jump in the predecessor
; should then get the right hint (not_taken or ":nt")
@j = external global i32
define i32 @foo(i32 %a) nounwind {
; CHECK: if{{ *}}(!p{{[0-3]}}.new) jump:nt
entry:
%tobool = icmp eq i32 %a, 0
br i1 %tobool, label %if.else, label %if.then, !prof !0
if.then: ; preds = %entry
%add = add nsw i32 %a, 10
%call = tail call i32 bitcast (i32 (...)* @foobar to i32 (i32)*)(i32 %add) nounwind
br label %return
if.else: ; preds = %entry
%call2 = tail call i32 bitcast (i32 (...)* @foobar to i32 (i32)*)(i32 4) nounwind
br label %return
return: ; preds = %if.else, %if.then
%retval.0 = phi i32 [ %call, %if.then ], [ %call2, %if.else ]
ret i32 %retval.0
}
declare i32 @foobar(...)
define i32 @bar(i32 %a) nounwind {
; CHECK: if{{ *}}(p{{[0-3]}}.new) jump:nt
entry:
%tobool = icmp eq i32 %a, 0
br i1 %tobool, label %if.else, label %if.then, !prof !1
if.then: ; preds = %entry
%add = add nsw i32 %a, 10
%call = tail call i32 bitcast (i32 (...)* @foobar to i32 (i32)*)(i32 %add) nounwind
br label %return
if.else: ; preds = %entry
%call2 = tail call i32 bitcast (i32 (...)* @foobar to i32 (i32)*)(i32 4) nounwind
br label %return
return: ; preds = %if.else, %if.then
%retval.0 = phi i32 [ %call, %if.then ], [ %call2, %if.else ]
ret i32 %retval.0
}
define i32 @foo_bar(i32 %a, i16 signext %b) nounwind {
; CHECK: if{{ *}}(!cmp.eq(r{{[0-9]*}}.new, #0)) jump:nt
entry:
%0 = load i32* @j, align 4, !tbaa !2
%tobool = icmp eq i32 %0, 0
br i1 %tobool, label %if.else, label %if.then, !prof !0
if.then: ; preds = %entry
%add = add nsw i32 %a, 10
%call = tail call i32 bitcast (i32 (...)* @foobar to i32 (i32)*)(i32 %add) nounwind
br label %return
if.else: ; preds = %entry
%add1 = add nsw i32 %a, 4
%call2 = tail call i32 bitcast (i32 (...)* @foobar to i32 (i32)*)(i32 %add1) nounwind
br label %return
return: ; preds = %if.else, %if.then
%retval.0 = phi i32 [ %call, %if.then ], [ %call2, %if.else ]
ret i32 %retval.0
}
!0 = metadata !{metadata !"branch_weights", i32 64, i32 4}
!1 = metadata !{metadata !"branch_weights", i32 4, i32 64}
!2 = metadata !{metadata !"int", metadata !3}
!3 = metadata !{metadata !"omnipotent char", metadata !4}
!4 = metadata !{metadata !"Simple C/C++ TBAA"}