Check against umin while converting fcmp into an icmp.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150425 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Devang Patel 2012-02-13 23:05:18 +00:00
parent a3b08d68bd
commit a2e0f6b643
2 changed files with 46 additions and 0 deletions

View File

@ -2714,6 +2714,17 @@ Instruction *InstCombiner::FoldFCmp_IntToFP_Cst(FCmpInst &I,
return ReplaceInstUsesWith(I, ConstantInt::getTrue(I.getContext()));
return ReplaceInstUsesWith(I, ConstantInt::getFalse(I.getContext()));
}
} else {
// See if the RHS value is < UnsignedMin.
APFloat SMin(RHS.getSemantics(), APFloat::fcZero, false);
SMin.convertFromAPInt(APInt::getMinValue(IntWidth), true,
APFloat::rmNearestTiesToEven);
if (SMin.compare(RHS) == APFloat::cmpGreaterThan) { // umin > 12312.0
if (Pred == ICmpInst::ICMP_NE || Pred == ICmpInst::ICMP_UGT ||
Pred == ICmpInst::ICMP_UGE)
return ReplaceInstUsesWith(I, ConstantInt::getTrue(I.getContext()));
return ReplaceInstUsesWith(I, ConstantInt::getFalse(I.getContext()));
}
}
// Okay, now we know that the FP constant fits in the range [SMIN, SMAX] or

View File

@ -0,0 +1,35 @@
; RUN: opt -instcombine -S < %s | FileCheck %s
; Radar 10803727
@.str = private unnamed_addr constant [35 x i8] c"\0Ain_range input (should be 0): %f\0A\00", align 1
@.str1 = external hidden unnamed_addr constant [35 x i8], align 1
declare i32 @printf(i8*, ...)
define i64 @_Z8tempCastj(i32 %val) uwtable ssp {
entry:
%call = call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([35 x i8]* @.str1, i64 0, i64 0), i32 %val)
%conv = uitofp i32 %val to double
%call.i = call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([35 x i8]* @.str, i64 0, i64 0), double %conv)
%cmp.i = fcmp oge double %conv, -1.000000e+00
br i1 %cmp.i, label %land.rhs.i, label %if.end.critedge
; CHECK: br i1 true, label %land.rhs.i, label %if.end.critedge
land.rhs.i: ; preds = %entry
%cmp1.i = fcmp olt double %conv, 1.000000e+00
br i1 %cmp1.i, label %if.then, label %if.end
if.then: ; preds = %land.rhs.i
%add = fadd double %conv, 5.000000e-01
%conv3 = fptosi double %add to i64
br label %return
if.end.critedge: ; preds = %entry
br label %if.end
if.end: ; preds = %if.end.critedge, %land.rhs.i
br label %return
return: ; preds = %if.end, %if.then
%retval.0 = phi i64 [ %conv3, %if.then ], [ -1, %if.end ]
ret i64 %retval.0
}