SpeculativeExecution: Allow speculating casts

[arsenm]

Merge with other patch

lib/Transforms/Scalar/SpeculativeExecution.cpp

switch (Operator::getOpcode(I)) {
     case Instruction::Shl:
     case Instruction::Sub:
     case Instruction::LShr:
     case Instruction::AShr:
     case Instruction::Xor:
     case Instruction::ZExt:
     case Instruction::SExt:
     case Instruction::Call:
+    case Instruction::BitCast:
+    case Instruction::PtrToInt:
+    case Instruction::IntToPtr:
+    case Instruction::AddrSpaceCast:
+    case Instruction::FPToUI:
+    case Instruction::FPToSI:
+    case Instruction::UIToFP:
+    case Instruction::SIToFP:
+    case Instruction::FPExt:
+    case Instruction::FPTrunc:
       return TTI.getUserCost(I);
 
     default:
       return UINT_MAX; // Disallow anything not whitelisted.
   }
 }
 
 bool SpeculativeExecutionPass::considerHoistingFromTo(

test/Transforms/SpeculativeExecution/spec-casts.ll

+; RUN: opt < %s -S -speculative-execution \
+; RUN:   -spec-exec-max-speculation-cost 4 -spec-exec-max-not-hoisted 3 \
+; RUN:   | FileCheck %s
+
+; CHECK-LABEL: @ifThen_bitcast(
+; CHECK: bitcast
+; CHECK: br i1 true
+define void @ifThen_bitcast() {
+  br i1 true, label %a, label %b
+
+a:
+  %x = bitcast i32 undef to float
+  br label %b
+
+b:
+  ret void
+}
+
+; CHECK-LABEL: @ifThen_ptrtoint(
+; CHECK: ptrtoint
+; CHECK: br i1 true
+define void @ifThen_ptrtoint() {
+  br i1 true, label %a, label %b
+
+a:
+  %x = ptrtoint i32* undef to i64
+  br label %b
+
+b:
+  ret void
+}
+
+; CHECK-LABEL: @ifThen_inttoptr(
+; CHECK: inttoptr
+; CHECK: br i1 true
+define void @ifThen_inttoptr() {
+  br i1 true, label %a, label %b
+
+a:
+  %x = inttoptr i64 undef to i32*
+  br label %b
+
+b:
+  ret void
+}
+
+; CHECK-LABEL: @ifThen_addrspacecast(
+; CHECK: addrspacecast
+; CHECK: br i1 true
+define void @ifThen_addrspacecast() {
+  br i1 true, label %a, label %b
+a:
+  %x = addrspacecast i32* undef to i32 addrspace(1)*
+  br label %b
+
+b:
+  ret void
+}
+
+; CHECK-LABEL: @ifThen_fptoui(
+; CHECK: fptoui
+; CHECK: br i1 true
+define void @ifThen_fptoui() {
+  br i1 true, label %a, label %b
+a:
+  %x = fptoui float undef to i32
+  br label %b
+
+b:
+  ret void
+}
+
+; CHECK-LABEL: @ifThen_fptosi(
+; CHECK: fptosi
+; CHECK: br i1 true
+define void @ifThen_fptosi() {
+  br i1 true, label %a, label %b
+a:
+  %x = fptosi float undef to i32
+  br label %b
+
+b:
+  ret void
+}
+
+; CHECK-LABEL: @ifThen_uitofp(
+; CHECK: uitofp
+; CHECK: br i1 true
+define void @ifThen_uitofp() {
+  br i1 true, label %a, label %b
+a:
+  %x = uitofp i32 undef to float
+  br label %b
+
+b:
+  ret void
+}
+
+; CHECK-LABEL: @ifThen_sitofp(
+; CHECK: sitofp
+; CHECK: br i1 true
+define void @ifThen_sitofp() {
+  br i1 true, label %a, label %b
+a:
+  %x = sitofp i32 undef to float
+  br label %b
+
+b:
+  ret void
+}
+
+; CHECK-LABEL: @ifThen_fpext(
+; CHECK: fpext
+; CHECK: br i1 true
+define void @ifThen_fpext() {
+  br i1 true, label %a, label %b
+a:
+  %x = fpext float undef to double
+  br label %b
+
+b:
+  ret void
+}
+
+; CHECK-LABEL: @ifThen_fptrunc(
+; CHECK: fptrunc
+; CHECK: br i1 true
+define void @ifThen_fptrunc() {
+  br i1 true, label %a, label %b
+a:
+  %x = fptrunc double undef to float
+  br label %b
+
+b:
+  ret void
+}