Add combiner patterns to more effectively utilize the BFI (bitfield insert)

instruction for non-constant operands. This includes the case referenced
in the README.txt regarding a bitfield copy.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108608 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Jim Grosbach
2010-07-17 03:30:54 +00:00
parent 879259faa3
commit 5423856e44
4 changed files with 114 additions and 37 deletions

View File

@@ -15,3 +15,26 @@ entry:
store i32 %2, i32* bitcast (%struct.F* @X to i32*), align 4
ret void
}
define i32 @f2(i32 %A, i32 %B) nounwind readnone optsize {
entry:
; CHECK: f2
; CHECK: mov r1, r1, lsr #7
; CHECK: bfi r0, r1, #7, #16
%and = and i32 %A, -8388481 ; <i32> [#uses=1]
%and2 = and i32 %B, 8388480 ; <i32> [#uses=1]
%or = or i32 %and2, %and ; <i32> [#uses=1]
ret i32 %or
}
define i32 @f3(i32 %A, i32 %B) nounwind readnone optsize {
entry:
; CHECK: f3
; CHECK: mov r2, r0, lsr #7
; CHECK: mov r0, r1
; CHECK: bfi r0, r2, #7, #16
%and = and i32 %A, 8388480 ; <i32> [#uses=1]
%and2 = and i32 %B, -8388481 ; <i32> [#uses=1]
%or = or i32 %and2, %and ; <i32> [#uses=1]
ret i32 %or
}