Move some former testcases (low-probability codegen

optimizations) into this wishlist.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59455 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Dale Johannesen 2008-11-17 18:56:34 +00:00
parent b8c564f72e
commit a7647e68a4

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@ -752,3 +752,48 @@ LBB2_1: ; bb
The 'mr' could be eliminated to folding the add into the cmp better.
//===---------------------------------------------------------------------===//
Codegen for the following (low-probability) case deteriorated considerably
when the correctness fixes for unordered comparisons went in (PR 642, 58871).
It should be possible to recover the code quality described in the comments.
; RUN: llvm-as < %s | llc -march=ppc32 | grep or | count 3
; This should produce one 'or' or 'cror' instruction per function.
; RUN: llvm-as < %s | llc -march=ppc32 | grep mfcr | count 3
; PR2964
define i32 @test(double %x, double %y) nounwind {
entry:
%tmp3 = fcmp ole double %x, %y ; <i1> [#uses=1]
%tmp345 = zext i1 %tmp3 to i32 ; <i32> [#uses=1]
ret i32 %tmp345
}
define i32 @test2(double %x, double %y) nounwind {
entry:
%tmp3 = fcmp one double %x, %y ; <i1> [#uses=1]
%tmp345 = zext i1 %tmp3 to i32 ; <i32> [#uses=1]
ret i32 %tmp345
}
define i32 @test3(double %x, double %y) nounwind {
entry:
%tmp3 = fcmp ugt double %x, %y ; <i1> [#uses=1]
%tmp34 = zext i1 %tmp3 to i32 ; <i32> [#uses=1]
ret i32 %tmp34
}
//===----------------------------------------------------------------------===//
; RUN: llvm-as < %s | llc -march=ppc32 | not grep fneg
; This could generate FSEL with appropriate flags (FSEL is not IEEE-safe, and
; should not be generated except with -enable-finite-only-fp-math or the like).
; With the correctness fixes for PR642 (58871) LowerSELECT_CC would need to
; recognize a more elaborate tree than a simple SETxx.
define double @test_FNEG_sel(double %A, double %B, double %C) {
%D = sub double -0.000000e+00, %A ; <double> [#uses=1]
%Cond = fcmp ugt double %D, -0.000000e+00 ; <i1> [#uses=1]
%E = select i1 %Cond, double %B, double %C ; <double> [#uses=1]
ret double %E
}