llvm-6502/test/CodeGen/Generic/MachineBranchProb.ll
Manman Ren 1a710fdde1 BranchProb: modify the definition of an edge in BranchProbabilityInfo to handle
the case of multiple edges from one block to another.

A simple example is a switch statement with multiple values to the same
destination. The definition of an edge is modified from a pair of blocks to
a pair of PredBlock and an index into the successors.

Also set the weight correctly when building SelectionDAG from LLVM IR,
especially when converting a Switch.
IntegersSubsetMapping is updated to calculate the weight for each cluster.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162572 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-24 18:14:27 +00:00

33 lines
969 B
LLVM

; RUN: llc < %s -print-machineinstrs=expand-isel-pseudos -o /dev/null 2>&1 | FileCheck %s
; Make sure we have the correct weight attached to each successor.
define i32 @test2(i32 %x) nounwind uwtable readnone ssp {
; CHECK: Machine code for function test2:
entry:
%conv = sext i32 %x to i64
switch i64 %conv, label %return [
i64 0, label %sw.bb
i64 1, label %sw.bb
i64 4, label %sw.bb
i64 5, label %sw.bb1
], !prof !0
; CHECK: BB#0: derived from LLVM BB %entry
; CHECK: Successors according to CFG: BB#2(64) BB#4(14)
; CHECK: BB#4: derived from LLVM BB %entry
; CHECK: Successors according to CFG: BB#1(10) BB#5(4)
; CHECK: BB#5: derived from LLVM BB %entry
; CHECK: Successors according to CFG: BB#1(4) BB#3(7)
sw.bb:
br label %return
sw.bb1:
br label %return
return:
%retval.0 = phi i32 [ 5, %sw.bb1 ], [ 1, %sw.bb ], [ 0, %entry ]
ret i32 %retval.0
}
!0 = metadata !{metadata !"branch_weights", i32 7, i32 6, i32 4, i32 4, i32 64}