llvm-6502/test/CodeGen/X86/jump_sign.ll
Evan Cheng d99d68bcee Fix two-address pass's aggressive instruction commuting heuristics. It's meant
to catch cases like:
 %reg1024<def> = MOV r1
 %reg1025<def> = MOV r0
 %reg1026<def> = ADD %reg1024, %reg1025
 r0            = MOV %reg1026

By commuting ADD, it let coalescer eliminate all of the copies. However, there
was a bug in the heuristics where it ended up commuting the ADD in:

 %reg1024<def> = MOV r0
 %reg1025<def> = MOV 0
 %reg1026<def> = ADD %reg1024, %reg1025
 r0            = MOV %reg1026

That did no benefit but rather ensure the last MOV would not be coalesced.

rdar://11355268


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156048 91177308-0d34-0410-b5e6-96231b3b80d8
2012-05-03 01:45:13 +00:00

86 lines
1.7 KiB
LLVM

; RUN: llc < %s -march=x86 -mcpu=pentiumpro | FileCheck %s
define i32 @f(i32 %X) {
entry:
; CHECK: f:
; CHECK: jns
%tmp1 = add i32 %X, 1 ; <i32> [#uses=1]
%tmp = icmp slt i32 %tmp1, 0 ; <i1> [#uses=1]
br i1 %tmp, label %cond_true, label %cond_next
cond_true: ; preds = %entry
%tmp2 = tail call i32 (...)* @bar( ) ; <i32> [#uses=0]
br label %cond_next
cond_next: ; preds = %cond_true, %entry
%tmp3 = tail call i32 (...)* @baz( ) ; <i32> [#uses=0]
ret i32 undef
}
declare i32 @bar(...)
declare i32 @baz(...)
; rdar://10633221
; rdar://11355268
define i32 @g(i32 %a, i32 %b) nounwind {
entry:
; CHECK: g:
; CHECK-NOT: test
; CHECK: cmovs
%sub = sub nsw i32 %a, %b
%cmp = icmp sgt i32 %sub, 0
%cond = select i1 %cmp, i32 %sub, i32 0
ret i32 %cond
}
; rdar://10734411
define i32 @h(i32 %a, i32 %b) nounwind {
entry:
; CHECK: h:
; CHECK-NOT: cmp
; CHECK: cmov
; CHECK-NOT: movl
; CHECK: ret
%cmp = icmp slt i32 %b, %a
%sub = sub nsw i32 %a, %b
%cond = select i1 %cmp, i32 %sub, i32 0
ret i32 %cond
}
define i32 @i(i32 %a, i32 %b) nounwind {
entry:
; CHECK: i:
; CHECK-NOT: cmp
; CHECK: cmov
; CHECK-NOT: movl
; CHECK: ret
%cmp = icmp sgt i32 %a, %b
%sub = sub nsw i32 %a, %b
%cond = select i1 %cmp, i32 %sub, i32 0
ret i32 %cond
}
define i32 @j(i32 %a, i32 %b) nounwind {
entry:
; CHECK: j:
; CHECK-NOT: cmp
; CHECK: cmov
; CHECK-NOT: movl
; CHECK: ret
%cmp = icmp ugt i32 %a, %b
%sub = sub i32 %a, %b
%cond = select i1 %cmp, i32 %sub, i32 0
ret i32 %cond
}
define i32 @k(i32 %a, i32 %b) nounwind {
entry:
; CHECK: k:
; CHECK-NOT: cmp
; CHECK: cmov
; CHECK-NOT: movl
; CHECK: ret
%cmp = icmp ult i32 %b, %a
%sub = sub i32 %a, %b
%cond = select i1 %cmp, i32 %sub, i32 0
ret i32 %cond
}