Don't generate libcalls for wide shift on Windows ARM (PR42711)

zmodem · zmodem · commit 882720b7ce33 · 2020-02-25T11:54:51.000+01:00
The previous patch (cff90f0) didn't cover ARM. (cherry picked from commit decd021)
diff --git a/llvm/lib/Target/ARM/ARMISelLowering.cpp b/llvm/lib/Target/ARM/ARMISelLowering.cpp
@@ -16892,7 +16892,7 @@ bool ARMTargetLowering::isCheapToSpeculateCtlz() const {
 }
 
 bool ARMTargetLowering::shouldExpandShift(SelectionDAG &DAG, SDNode *N) const {
-  return !Subtarget->hasMinSize();
+  return !Subtarget->hasMinSize() || Subtarget->isTargetWindows();
 }
 
 Value *ARMTargetLowering::emitLoadLinked(IRBuilder<> &Builder, Value *Addr,
diff --git a/llvm/test/CodeGen/ARM/shift_minsize.ll b/llvm/test/CodeGen/ARM/shift_minsize.ll
@@ -1,4 +1,10 @@
-; RUN: llc -mtriple=arm-eabi %s -o - | FileCheck %s
+; RUN: llc -mtriple=arm-eabi        %s -o - | FileCheck %s
+; RUN: llc -mtriple=thumbv7-windows %s -o - | FileCheck %s -check-prefix=CHECK-WIN
+
+; The Windows runtime doesn't have these.
+; CHECK-WIN-NOT: __ashldi3
+; CHECK-WIN-NOT: __ashrdi3
+; CHECK-WIN-NOT: __lshrdi3
 
 define i64 @f0(i64 %val, i64 %amt) minsize optsize {
 ; CHECK-LABEL:   f0:

Original file line number	Diff line number	Diff line change
`@@ -16892,7 +16892,7 @@ bool ARMTargetLowering::isCheapToSpeculateCtlz() const {`
`16892`	`16892`	`}`
`16893`	`16893`
`16894`	`16894`	`bool ARMTargetLowering::shouldExpandShift(SelectionDAG &DAG, SDNode *N) const {`
`16895`		`- return !Subtarget->hasMinSize();`
	`16895`	`+ return !Subtarget->hasMinSize() \|\| Subtarget->isTargetWindows();`
`16896`	`16896`	`}`
`16897`	`16897`
`16898`	`16898`	`Value ARMTargetLowering::emitLoadLinked(IRBuilder<> &Builder, Value Addr,`