Commit Graph

2 Commits

Author SHA1 Message Date
Li Jia He bcae407a3c [PowerPC] Fix a conversion is not considered when the ISD::BR_CC node making the instruction selection
Summary:
 A signed comparison of i1 values produces the opposite result to an unsigned one if the condition code 
 includes less-than or greater-than. This is so because 1 is the most negative signed i1 number and the 
 most positive unsigned i1 number. The CR-logical operations used for such comparisons are non-commutative
 so for signed comparisons vs. unsigned ones, the input operands just need to be swapped.

Reviewed By: steven.zhang

Differential Revision: https://reviews.llvm.org/D54825

llvm-svn: 347831
2018-11-29 03:04:39 +00:00
Li Jia He 339af52804 [PowerPC] [NFC] Add test cases to the ISD::BR_CC node in the instruction selection
Add the following test case for the ISD::BR_CC node in the instruction selection
define i64 @testi64slt(i64 %c1, i64 %c2, i64 %c3, i64 %c4, i64 %a1, i64 %a2) #0 {
entry:
  %cmp1 = icmp eq i64 %c3, %c4
  %cmp3tmp = icmp eq i64 %c1, %c2
  %cmp3 = icmp slt i1 %cmp3tmp, %cmp1
  br i1 %cmp3, label %iftrue, label %iffalse
iftrue:
  ret i64 %a1
iffalse:
  ret i64 %a2
}
The data type i64 can be replaced by i32, i64, float, double

And condition codes can be replaced by: SETEQ, SETEN, SELT, SETLE, SETGT, SETGE,SETULT, SETULE, SSETGT, and SETUGE

Reviewed By: steven.zhang

Differential Revision: https://reviews.llvm.org/D54824

llvm-svn: 347828
2018-11-29 02:51:03 +00:00