const TargetRegisterClass *RC = TLI.getRegClassFor(RetVT);
bool NeedTest = true;
- // Optimize conditons coming from a compare.
- if (const auto *CI = dyn_cast<CmpInst>(Cond)) {
+ // Optimize conditons coming from a compare if both instructions are in the
+ // same basic block (values defined in other basic blocks may not have
+ // initialized registers).
+ const auto *CI = dyn_cast<CmpInst>(Cond);
+ if (CI && (CI->getParent() == I->getParent())) {
CmpInst::Predicate Predicate = optimizeCmpPredicate(CI);
// FCMP_OEQ and FCMP_UNE cannot be checked with a single instruction.
if (!isTypeLegal(I->getType(), RetVT))
return false;
+ // Optimize conditons coming from a compare if both instructions are in the
+ // same basic block (values defined in other basic blocks may not have
+ // initialized registers).
const auto *CI = dyn_cast<FCmpInst>(I->getOperand(0));
- if (!CI)
+ if (!CI || (CI->getParent() != I->getParent()))
return false;
if (I->getType() != CI->getOperand(0)->getType() ||
const Value *Cond = I->getOperand(0);
X86::CondCode CC = X86::COND_NE;
- // Don't emit a test if the condition comes from a compare.
- if (const auto *CI = dyn_cast<CmpInst>(Cond)) {
+
+ // Optimize conditons coming from a compare if both instructions are in the
+ // same basic block (values defined in other basic blocks may not have
+ // initialized registers).
+ const auto *CI = dyn_cast<CmpInst>(Cond);
+ if (CI && (CI->getParent() == I->getParent())) {
bool NeedSwap;
std::tie(CC, NeedSwap) = getX86ConditonCode(CI->getPredicate());
if (CC > X86::LAST_VALID_COND)
--- /dev/null
+; RUN: llc < %s -O0 -mtriple=x86_64-apple-darwin10 | FileCheck %s
+
+; Test if we do not fold the cmp into select if the instructions are in
+; different basic blocks.
+
+define i32 @select_cmp_cmov_i32(i32 %a, i32 %b) {
+; CHECK-LABEL: select_cmp_cmov_i32
+; CHECK-LABEL: continue
+; CHECK-NOT: cmp
+ %1 = icmp ult i32 %a, %b
+ br i1 %1, label %continue, label %exit
+
+continue:
+ %2 = select i1 %1, i32 %a, i32 %b
+ ret i32 %2
+
+exit:
+ ret i32 -1
+}
+
+define float @select_fcmp_oeq_f32(float %a, float %b, float %c, float %d) {
+; CHECK-LABEL: select_fcmp_oeq_f32
+; CHECK-LABEL: continue
+; CHECK-NOT: cmp
+ %1 = fcmp oeq float %a, %b
+ br i1 %1, label %continue, label %exit
+
+continue:
+ %2 = select i1 %1, float %c, float %d
+ ret float %2
+
+exit:
+ ret float -1.0
+}
+
+define float @select_fcmp_one_f32(float %a, float %b, float %c, float %d) {
+; CHECK-LABEL: select_fcmp_one_f32
+; CHECK-LABEL: continue
+; CHECK-NOT: ucomi
+ %1 = fcmp one float %a, %b
+ br i1 %1, label %continue, label %exit
+
+continue:
+ %2 = select i1 %1, float %c, float %d
+ ret float %2
+
+exit:
+ ret float -1.0
+}
+