[ARM GlobalISel] Support integer division for Thumb2

Support G_SDIV, G_UDIV, G_SREM and G_UREM.

The only significant difference between arm and thumb mode is that we
need to check a different subtarget feature.

llvm-svn: 352346

1 files changed, 21 insertions, 19 deletions

diff --git a/llvm/lib/Target/ARM/ARMLegalizerInfo.cpp b/llvm/lib/Target/ARM/ARMLegalizerInfo.cpp
index 9a8da31d7b3..943cabd4f33 100644
--- a/llvm/lib/Target/ARM/ARMLegalizerInfo.cpp
+++ b/llvm/lib/Target/ARM/ARMLegalizerInfo.cpp
@@ -92,6 +92,27 @@ ARMLegalizerInfo::ARMLegalizerInfo(const ARMSubtarget &ST) {
     .legalFor({{s32, s32}})
     .clampScalar(1, s32, s32);
 
+  bool HasHWDivide = (!ST.isThumb() && ST.hasDivideInARMMode()) ||
+                     (ST.isThumb() && ST.hasDivideInThumbMode());
+  if (HasHWDivide)
+    getActionDefinitionsBuilder({G_SDIV, G_UDIV})
+        .legalFor({s32})
+        .clampScalar(0, s32, s32);
+  else
+    getActionDefinitionsBuilder({G_SDIV, G_UDIV})
+        .libcallFor({s32})
+        .clampScalar(0, s32, s32);
+
+  for (unsigned Op : {G_SREM, G_UREM}) {
+    setLegalizeScalarToDifferentSizeStrategy(Op, 0, widen_8_16);
+    if (HasHWDivide)
+      setAction({Op, s32}, Lower);
+    else if (AEABI(ST))
+      setAction({Op, s32}, Custom);
+    else
+      setAction({Op, s32}, Libcall);
+  }
+
   getActionDefinitionsBuilder(G_INTTOPTR).legalFor({{p0, s32}});
   getActionDefinitionsBuilder(G_PTRTOINT).legalFor({{s32, p0}});
 
@@ -120,25 +141,6 @@ ARMLegalizerInfo::ARMLegalizerInfo(const ARMSubtarget &ST) {
   getActionDefinitionsBuilder(G_GLOBAL_VALUE).legalFor({p0});
   getActionDefinitionsBuilder(G_FRAME_INDEX).legalFor({p0});
 
-  if (ST.hasDivideInARMMode())
-    getActionDefinitionsBuilder({G_SDIV, G_UDIV})
-        .legalFor({s32})
-        .clampScalar(0, s32, s32);
-  else
-    getActionDefinitionsBuilder({G_SDIV, G_UDIV})
-        .libcallFor({s32})
-        .clampScalar(0, s32, s32);
-
-  for (unsigned Op : {G_SREM, G_UREM}) {
-    setLegalizeScalarToDifferentSizeStrategy(Op, 0, widen_8_16);
-    if (ST.hasDivideInARMMode())
-      setAction({Op, s32}, Lower);
-    else if (AEABI(ST))
-      setAction({Op, s32}, Custom);
-    else
-      setAction({Op, s32}, Libcall);
-  }
-
   if (ST.hasV5TOps()) {
     getActionDefinitionsBuilder(G_CTLZ)
         .legalFor({s32})