[AArch64][GlobalISel] Legalize narrow scalar fp->int conversions.

Since we're now avoiding operations using narrow scalar integer types,
we have to legalize the integer side of the FP conversions.

This requires teaching the legalizer how to do that.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292828 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/GlobalISel/LegalizerHelper.cpp b/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
index f77d807a69de04cdf7b5c4e9af5e7e0525f7af32..6da02646250beeca455200c9b1ad187fceff0282 100644 (file)
--- a/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
+++ b/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
@@ -273,6 +273,20 @@ LegalizerHelper::widenScalar(MachineInstr &MI, unsigned TypeIdx, LLT WideTy) {
     MI.eraseFromParent();
     return Legalized;
   }
+  case TargetOpcode::G_FPTOSI:
+  case TargetOpcode::G_FPTOUI: {
+    if (TypeIdx != 0)
+      return UnableToLegalize;
+
+    unsigned DstExt = MRI.createGenericVirtualRegister(WideTy);
+    MIRBuilder.buildInstr(MI.getOpcode())
+        .addDef(DstExt)
+        .addUse(MI.getOperand(1).getReg());
+
+    MIRBuilder.buildTrunc(MI.getOperand(0).getReg(), DstExt);
+    MI.eraseFromParent();
+    return Legalized;
+  }
   case TargetOpcode::G_SITOFP:
   case TargetOpcode::G_UITOFP: {
     if (TypeIdx != 1)

diff --git a/lib/Target/AArch64/AArch64LegalizerInfo.cpp b/lib/Target/AArch64/AArch64LegalizerInfo.cpp
index 985260700e351b2bbf70179c49d72a3a186b7d5f..871556c8ed9c3ca886943a1dee3ccc4eb985d9a0 100644 (file)
--- a/lib/Target/AArch64/AArch64LegalizerInfo.cpp
+++ b/lib/Target/AArch64/AArch64LegalizerInfo.cpp
@@ -151,9 +151,8 @@ AArch64LegalizerInfo::AArch64LegalizerInfo() {
     setAction({G_UITOFP, 1, Ty}, Legal);
   }
   for (auto Ty : { s1, s8, s16 }) {
-    // FIXME: These should be widened on types smaller than s32.
-    setAction({G_FPTOSI, 0, Ty}, Legal);
-    setAction({G_FPTOUI, 0, Ty}, Legal);
+    setAction({G_FPTOSI, 0, Ty}, WidenScalar);
+    setAction({G_FPTOUI, 0, Ty}, WidenScalar);
     setAction({G_SITOFP, 1, Ty}, WidenScalar);
     setAction({G_UITOFP, 1, Ty}, WidenScalar);
   }

diff --git a/test/CodeGen/AArch64/GlobalISel/legalize-fptoi.mir b/test/CodeGen/AArch64/GlobalISel/legalize-fptoi.mir
index 968256c7424b4e566445ebebdf1a0e2cce607159..8d0af0dc447c0c4e978e3ecf5e51affdfc6925b6 100644 (file)
--- a/test/CodeGen/AArch64/GlobalISel/legalize-fptoi.mir
+++ b/test/CodeGen/AArch64/GlobalISel/legalize-fptoi.mir
@@ -130,7 +130,8 @@ body: |
     %0:_(s32) = COPY %w0
 
     ; CHECK-LABEL: name: test_fptosi_s1_s32
-    ; CHECK: %1(s1) = G_FPTOSI %0
+    ; CHECK: %2(s32) = G_FPTOSI %0
+    ; CHECK: %1(s1) = G_TRUNC %2
     %1:_(s1) = G_FPTOSI %0
 ...
 
@@ -142,7 +143,8 @@ body: |
     %0:_(s32) = COPY %w0
 
     ; CHECK-LABEL: name: test_fptoui_s1_s32
-    ; CHECK: %1(s1) = G_FPTOUI %0
+    ; CHECK: %2(s32) = G_FPTOUI %0
+    ; CHECK: %1(s1) = G_TRUNC %2
     %1:_(s1) = G_FPTOUI %0
 ...
 
@@ -154,7 +156,8 @@ body: |
     %0:_(s64) = COPY %x0
 
     ; CHECK-LABEL: name: test_fptosi_s8_s64
-    ; CHECK: %1(s8) = G_FPTOSI %0
+    ; CHECK: %2(s32) = G_FPTOSI %0
+    ; CHECK: %1(s8) = G_TRUNC %2
     %1:_(s8) = G_FPTOSI %0
 ...
 
@@ -166,7 +169,8 @@ body: |
     %0:_(s64) = COPY %x0
 
     ; CHECK-LABEL: name: test_fptoui_s8_s64
-    ; CHECK: %1(s8) = G_FPTOUI %0
+    ; CHECK: %2(s32) = G_FPTOUI %0
+    ; CHECK: %1(s8) = G_TRUNC %2
     %1:_(s8) = G_FPTOUI %0
 ...
 
@@ -178,7 +182,8 @@ body: |
     %0:_(s32) = COPY %w0
 
     ; CHECK-LABEL: name: test_fptosi_s16_s32
-    ; CHECK: %1(s16) = G_FPTOSI %0
+    ; CHECK: %2(s32) = G_FPTOSI %0
+    ; CHECK: %1(s16) = G_TRUNC %2
     %1:_(s16) = G_FPTOSI %0
 ...
 
@@ -190,6 +195,7 @@ body: |
     %0:_(s32) = COPY %w0
 
     ; CHECK-LABEL: name: test_fptoui_s16_s32
-    ; CHECK: %1(s16) = G_FPTOUI %0
+    ; CHECK: %2(s32) = G_FPTOUI %0
+    ; CHECK: %1(s16) = G_TRUNC %2
     %1:_(s16) = G_FPTOUI %0
 ...