[llvm-commits] [llvm] r72300 - in /llvm/trunk: lib/Transforms/Scalar/InstructionCombining.cpp test/Transforms/InstCombine/2009-05-23-FCmpToICmp.ll
Evan Cheng
evan.cheng at apple.com
Fri May 22 16:10:54 PDT 2009
Author: evancheng
Date: Fri May 22 18:10:53 2009
New Revision: 72300
URL: http://llvm.org/viewvc/llvm-project?rev=72300&view=rev
Log:
Fix bug in FoldFCmp_IntToFP_Cst. If inttofp is a uintofp, use unsigned instead of signed integer constant.
Added:
llvm/trunk/test/Transforms/InstCombine/2009-05-23-FCmpToICmp.ll
Modified:
llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp
Modified: llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp?rev=72300&r1=72299&r2=72300&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp Fri May 22 18:10:53 2009
@@ -5598,68 +5598,74 @@
// [0, UMAX], but it may still be fractional. See if it is fractional by
// casting the FP value to the integer value and back, checking for equality.
// Don't do this for zero, because -0.0 is not fractional.
- Constant *RHSInt = ConstantExpr::getFPToSI(RHSC, IntTy);
- if (!RHS.isZero() &&
- ConstantExpr::getSIToFP(RHSInt, RHSC->getType()) != RHSC) {
- // If we had a comparison against a fractional value, we have to adjust the
- // compare predicate and sometimes the value. RHSC is rounded towards zero
- // at this point.
- switch (Pred) {
- default: assert(0 && "Unexpected integer comparison!");
- case ICmpInst::ICMP_NE: // (float)int != 4.4 --> true
- return ReplaceInstUsesWith(I, ConstantInt::getTrue());
- case ICmpInst::ICMP_EQ: // (float)int == 4.4 --> false
- return ReplaceInstUsesWith(I, ConstantInt::getFalse());
- case ICmpInst::ICMP_ULE:
- // (float)int <= 4.4 --> int <= 4
- // (float)int <= -4.4 --> false
- if (RHS.isNegative())
- return ReplaceInstUsesWith(I, ConstantInt::getFalse());
- break;
- case ICmpInst::ICMP_SLE:
- // (float)int <= 4.4 --> int <= 4
- // (float)int <= -4.4 --> int < -4
- if (RHS.isNegative())
- Pred = ICmpInst::ICMP_SLT;
- break;
- case ICmpInst::ICMP_ULT:
- // (float)int < -4.4 --> false
- // (float)int < 4.4 --> int <= 4
- if (RHS.isNegative())
- return ReplaceInstUsesWith(I, ConstantInt::getFalse());
- Pred = ICmpInst::ICMP_ULE;
- break;
- case ICmpInst::ICMP_SLT:
- // (float)int < -4.4 --> int < -4
- // (float)int < 4.4 --> int <= 4
- if (!RHS.isNegative())
- Pred = ICmpInst::ICMP_SLE;
- break;
- case ICmpInst::ICMP_UGT:
- // (float)int > 4.4 --> int > 4
- // (float)int > -4.4 --> true
- if (RHS.isNegative())
- return ReplaceInstUsesWith(I, ConstantInt::getTrue());
- break;
- case ICmpInst::ICMP_SGT:
- // (float)int > 4.4 --> int > 4
- // (float)int > -4.4 --> int >= -4
- if (RHS.isNegative())
- Pred = ICmpInst::ICMP_SGE;
- break;
- case ICmpInst::ICMP_UGE:
- // (float)int >= -4.4 --> true
- // (float)int >= 4.4 --> int > 4
- if (!RHS.isNegative())
+ Constant *RHSInt = LHSUnsigned
+ ? ConstantExpr::getFPToUI(RHSC, IntTy)
+ : ConstantExpr::getFPToSI(RHSC, IntTy);
+ if (!RHS.isZero()) {
+ bool Equal = LHSUnsigned
+ ? ConstantExpr::getUIToFP(RHSInt, RHSC->getType()) == RHSC
+ : ConstantExpr::getSIToFP(RHSInt, RHSC->getType()) == RHSC;
+ if (!Equal) {
+ // If we had a comparison against a fractional value, we have to adjust
+ // the compare predicate and sometimes the value. RHSC is rounded towards
+ // zero at this point.
+ switch (Pred) {
+ default: assert(0 && "Unexpected integer comparison!");
+ case ICmpInst::ICMP_NE: // (float)int != 4.4 --> true
return ReplaceInstUsesWith(I, ConstantInt::getTrue());
- Pred = ICmpInst::ICMP_UGT;
- break;
- case ICmpInst::ICMP_SGE:
- // (float)int >= -4.4 --> int >= -4
- // (float)int >= 4.4 --> int > 4
- if (!RHS.isNegative())
- Pred = ICmpInst::ICMP_SGT;
- break;
+ case ICmpInst::ICMP_EQ: // (float)int == 4.4 --> false
+ return ReplaceInstUsesWith(I, ConstantInt::getFalse());
+ case ICmpInst::ICMP_ULE:
+ // (float)int <= 4.4 --> int <= 4
+ // (float)int <= -4.4 --> false
+ if (RHS.isNegative())
+ return ReplaceInstUsesWith(I, ConstantInt::getFalse());
+ break;
+ case ICmpInst::ICMP_SLE:
+ // (float)int <= 4.4 --> int <= 4
+ // (float)int <= -4.4 --> int < -4
+ if (RHS.isNegative())
+ Pred = ICmpInst::ICMP_SLT;
+ break;
+ case ICmpInst::ICMP_ULT:
+ // (float)int < -4.4 --> false
+ // (float)int < 4.4 --> int <= 4
+ if (RHS.isNegative())
+ return ReplaceInstUsesWith(I, ConstantInt::getFalse());
+ Pred = ICmpInst::ICMP_ULE;
+ break;
+ case ICmpInst::ICMP_SLT:
+ // (float)int < -4.4 --> int < -4
+ // (float)int < 4.4 --> int <= 4
+ if (!RHS.isNegative())
+ Pred = ICmpInst::ICMP_SLE;
+ break;
+ case ICmpInst::ICMP_UGT:
+ // (float)int > 4.4 --> int > 4
+ // (float)int > -4.4 --> true
+ if (RHS.isNegative())
+ return ReplaceInstUsesWith(I, ConstantInt::getTrue());
+ break;
+ case ICmpInst::ICMP_SGT:
+ // (float)int > 4.4 --> int > 4
+ // (float)int > -4.4 --> int >= -4
+ if (RHS.isNegative())
+ Pred = ICmpInst::ICMP_SGE;
+ break;
+ case ICmpInst::ICMP_UGE:
+ // (float)int >= -4.4 --> true
+ // (float)int >= 4.4 --> int > 4
+ if (!RHS.isNegative())
+ return ReplaceInstUsesWith(I, ConstantInt::getTrue());
+ Pred = ICmpInst::ICMP_UGT;
+ break;
+ case ICmpInst::ICMP_SGE:
+ // (float)int >= -4.4 --> int >= -4
+ // (float)int >= 4.4 --> int > 4
+ if (!RHS.isNegative())
+ Pred = ICmpInst::ICMP_SGT;
+ break;
+ }
}
}
Added: llvm/trunk/test/Transforms/InstCombine/2009-05-23-FCmpToICmp.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/InstCombine/2009-05-23-FCmpToICmp.ll?rev=72300&view=auto
==============================================================================
--- llvm/trunk/test/Transforms/InstCombine/2009-05-23-FCmpToICmp.ll (added)
+++ llvm/trunk/test/Transforms/InstCombine/2009-05-23-FCmpToICmp.ll Fri May 22 18:10:53 2009
@@ -0,0 +1,9 @@
+; RUN: llvm-as < %s | opt -instcombine | llvm-dis | not grep cmp
+; rdar://6903175
+
+define i1 @f0(i32 *%a) nounwind {
+ %b = load i32* %a, align 4
+ %c = uitofp i32 %b to double
+ %d = fcmp ogt double %c, 0x41EFFFFFFFE00000
+ ret i1 %d
+}
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