From 7d97de60b3ecd52e2a427dff661cdd1ca99617e9 Mon Sep 17 00:00:00 2001
From: Jessica Paquette <jpaquette@apple.com>
Date: Tue, 3 Aug 2021 16:42:22 -0700
Subject: [PATCH] [AArch64][GlobalISel] Widen G_FPTO*I before clamping

Going through our legalization rules and doing some cleanup.

Widening and then clamping is usually easier than clamping and then widening.

This allows us to legalize some weird types like s88.

Differential Revision: https://reviews.llvm.org/D107413
---
 .../Target/AArch64/GISel/AArch64LegalizerInfo.cpp  |  6 +--
 .../CodeGen/AArch64/GlobalISel/legalize-fptoi.mir  | 45 ++++++++++++++++++++++
 2 files changed, 48 insertions(+), 3 deletions(-)

diff --git a/llvm/lib/Target/AArch64/GISel/AArch64LegalizerInfo.cpp b/llvm/lib/Target/AArch64/GISel/AArch64LegalizerInfo.cpp
index 2bd3889..279fdcf 100644
--- a/llvm/lib/Target/AArch64/GISel/AArch64LegalizerInfo.cpp
+++ b/llvm/lib/Target/AArch64/GISel/AArch64LegalizerInfo.cpp
@@ -459,10 +459,10 @@ AArch64LegalizerInfo::AArch64LegalizerInfo(const AArch64Subtarget &ST)
   // Conversions
   getActionDefinitionsBuilder({G_FPTOSI, G_FPTOUI})
       .legalForCartesianProduct({s32, s64, v2s64, v4s32, v2s32})
-      .clampScalar(0, s32, s64)
       .widenScalarToNextPow2(0)
-      .clampScalar(1, s32, s64)
-      .widenScalarToNextPow2(1);
+      .clampScalar(0, s32, s64)
+      .widenScalarToNextPow2(1)
+      .clampScalar(1, s32, s64);
 
   getActionDefinitionsBuilder({G_SITOFP, G_UITOFP})
       .legalForCartesianProduct({s32, s64, v2s64, v4s32, v2s32})
diff --git a/llvm/test/CodeGen/AArch64/GlobalISel/legalize-fptoi.mir b/llvm/test/CodeGen/AArch64/GlobalISel/legalize-fptoi.mir
index b2ee3a6..6b7b617 100644
--- a/llvm/test/CodeGen/AArch64/GlobalISel/legalize-fptoi.mir
+++ b/llvm/test/CodeGen/AArch64/GlobalISel/legalize-fptoi.mir
@@ -266,3 +266,48 @@ body: |
     %1:_(s128) = G_FPTOSI %0
     $q0 = COPY %1
 ...
+---
+name:            test_fptosi_s88_s88
+body: |
+  bb.0:
+    liveins: $x0
+    ; CHECK-LABEL: name: test_fptosi_s88_s88
+    ; CHECK: [[DEF:%[0-9]+]]:_(s88) = G_IMPLICIT_DEF
+    ; CHECK: [[FPTOSI:%[0-9]+]]:_(s128) = G_FPTOSI [[DEF]](s88)
+    ; CHECK: [[TRUNC:%[0-9]+]]:_(s88) = G_TRUNC [[FPTOSI]](s128)
+    ; CHECK: %trunc:_(s64) = G_TRUNC [[TRUNC]](s88)
+    ; CHECK: $x0 = COPY %trunc(s64)
+    %0:_(s88) = G_IMPLICIT_DEF
+    %1:_(s88) = G_FPTOSI %0
+    %trunc:_(s64) = G_TRUNC %1
+    $x0 = COPY %trunc
+...
+---
+name:            test_fptosi_s88_s64
+body: |
+  bb.0:
+    liveins: $x0
+    ; CHECK-LABEL: name: test_fptosi_s88_s64
+    ; CHECK: [[DEF:%[0-9]+]]:_(s64) = G_IMPLICIT_DEF
+    ; CHECK: [[FPTOSI:%[0-9]+]]:_(s128) = G_FPTOSI [[DEF]](s64)
+    ; CHECK: [[TRUNC:%[0-9]+]]:_(s88) = G_TRUNC [[FPTOSI]](s128)
+    ; CHECK: %trunc:_(s64) = G_TRUNC [[TRUNC]](s88)
+    ; CHECK: $x0 = COPY %trunc(s64)
+    %0:_(s64) = G_IMPLICIT_DEF
+    %1:_(s88) = G_FPTOSI %0
+    %trunc:_(s64) = G_TRUNC %1
+    $x0 = COPY %trunc
+...
+---
+name:            test_fptosi_s64_s88
+body: |
+  bb.0:
+    liveins: $x0
+    ; CHECK-LABEL: name: test_fptosi_s64_s88
+    ; CHECK: [[DEF:%[0-9]+]]:_(s88) = G_IMPLICIT_DEF
+    ; CHECK: [[FPEXT:%[0-9]+]]:_(s128) = G_FPEXT [[DEF]](s88)
+    ; CHECK: [[FPTOSI:%[0-9]+]]:_(s64) = G_FPTOSI [[FPEXT]](s128)
+    ; CHECK: $x0 = COPY [[FPTOSI]](s64)
+    %0:_(s88) = G_IMPLICIT_DEF
+    %1:_(s64) = G_FPTOSI %0
+    $x0 = COPY %1
-- 
2.7.4