1 files changed, 135 insertions, 0 deletions
diff --git a/llvm/test/Transforms/InstCombine/trunc.ll b/llvm/test/Transforms/InstCombine/trunc.ll
index 38f6b2804d6..3c101f65011 100644
--- a/llvm/test/Transforms/InstCombine/trunc.ll
+++ b/llvm/test/Transforms/InstCombine/trunc.ll
@@ -160,3 +160,138 @@ define i32 @trunc_bitcast3(<4 x i32> %v) {
 ; CHECK-NEXT:  ret i32 %ext
 }
 
+; CHECK-LABEL: @trunc_shl_31_i32_i64(
+; CHECK: %val.tr = trunc i64 %val to i32
+; CHECK-NEXT: shl i32 %val.tr, 31
+define i32 @trunc_shl_31_i32_i64(i64 %val) {
+  %shl = shl i64 %val, 31
+  %trunc = trunc i64 %shl to i32
+  ret i32 %trunc
+}
+
+; CHECK-LABEL: @trunc_shl_nsw_31_i32_i64(
+; CHECK: %val.tr = trunc i64 %val to i32
+; CHECK-NEXT: shl i32 %val.tr, 31
+define i32 @trunc_shl_nsw_31_i32_i64(i64 %val) {
+  %shl = shl nsw i64 %val, 31
+  %trunc = trunc i64 %shl to i32
+  ret i32 %trunc
+}
+
+; CHECK-LABEL: @trunc_shl_nuw_31_i32_i64(
+; CHECK: %val.tr = trunc i64 %val to i32
+; CHECK-NEXT: shl i32 %val.tr, 31
+define i32 @trunc_shl_nuw_31_i32_i64(i64 %val) {
+  %shl = shl nuw i64 %val, 31
+  %trunc = trunc i64 %shl to i32
+  ret i32 %trunc
+}
+
+; CHECK-LABEL: @trunc_shl_nsw_nuw_31_i32_i64(
+; CHECK: %val.tr = trunc i64 %val to i32
+; CHECK-NEXT: shl i32 %val.tr, 31
+define i32 @trunc_shl_nsw_nuw_31_i32_i64(i64 %val) {
+  %shl = shl nsw nuw i64 %val, 31
+  %trunc = trunc i64 %shl to i32
+  ret i32 %trunc
+}
+
+; CHECK-LABEL: @trunc_shl_15_i16_i64(
+; CHECK: %val.tr = trunc i64 %val to i16
+; CHECK-NEXT: shl i16 %val.tr, 15
+define i16 @trunc_shl_15_i16_i64(i64 %val) {
+  %shl = shl i64 %val, 15
+  %trunc = trunc i64 %shl to i16
+  ret i16 %trunc
+}
+
+; CHECK-LABEL: @trunc_shl_15_i16_i32(
+; CHECK: %val.tr = trunc i32 %val to i16
+; CHECK-NEXT: shl i16 %val.tr, 15
+define i16 @trunc_shl_15_i16_i32(i32 %val) {
+  %shl = shl i32 %val, 15
+  %trunc = trunc i32 %shl to i16
+  ret i16 %trunc
+}
+
+; CHECK-LABEL: @trunc_shl_7_i8_i64(
+; CHECK: %val.tr = trunc i64 %val to i8
+; CHECK-NEXT: shl i8 %val.tr, 7
+define i8 @trunc_shl_7_i8_i64(i64 %val) {
+  %shl = shl i64 %val, 7
+  %trunc = trunc i64 %shl to i8
+  ret i8 %trunc
+}
+
+; CHECK-LABEL: @trunc_shl_1_i2_i64(
+; CHECK: shl i64 %val, 1
+; CHECK-NEXT: trunc i64 %shl to i2
+define i2 @trunc_shl_1_i2_i64(i64 %val) {
+  %shl = shl i64 %val, 1
+  %trunc = trunc i64 %shl to i2
+  ret i2 %trunc
+}
+
+; CHECK-LABEL: @trunc_shl_1_i32_i64(
+; CHECK: %val.tr = trunc i64 %val to i32
+; CHECK-NEXT: shl i32 %val.tr, 1
+define i32 @trunc_shl_1_i32_i64(i64 %val) {
+  %shl = shl i64 %val, 1
+  %trunc = trunc i64 %shl to i32
+  ret i32 %trunc
+}
+
+; CHECK-LABEL: @trunc_shl_16_i32_i64(
+; CHECK: %val.tr = trunc i64 %val to i32
+; CHECK-NEXT: shl i32 %val.tr, 16
+define i32 @trunc_shl_16_i32_i64(i64 %val) {
+  %shl = shl i64 %val, 16
+  %trunc = trunc i64 %shl to i32
+  ret i32 %trunc
+}
+
+; CHECK-LABEL: @trunc_shl_33_i32_i64(
+; CHECK: ret i32 0
+define i32 @trunc_shl_33_i32_i64(i64 %val) {
+  %shl = shl i64 %val, 33
+  %trunc = trunc i64 %shl to i32
+  ret i32 %trunc
+}
+
+; CHECK-LABEL: @trunc_shl_32_i32_i64(
+; CHECK: ret i32 0
+define i32 @trunc_shl_32_i32_i64(i64 %val) {
+  %shl = shl i64 %val, 32
+  %trunc = trunc i64 %shl to i32
+  ret i32 %trunc
+}
+
+; TODO: Should be able to handle vectors
+; CHECK-LABEL: @trunc_shl_16_v2i32_v2i64(
+; CHECK: shl <2 x i64>
+define <2 x i32> @trunc_shl_16_v2i32_v2i64(<2 x i64> %val) {
+  %shl = shl <2 x i64> %val, <i64 16, i64 16>
+  %trunc = trunc <2 x i64> %shl to <2 x i32>
+  ret <2 x i32> %trunc
+}
+
+; CHECK-LABEL: @trunc_shl_nosplat_v2i32_v2i64(
+; CHECK: shl <2 x i64>
+define <2 x i32> @trunc_shl_nosplat_v2i32_v2i64(<2 x i64> %val) {
+  %shl = shl <2 x i64> %val, <i64 15, i64 16>
+  %trunc = trunc <2 x i64> %shl to <2 x i32>
+  ret <2 x i32> %trunc
+}
+
+; CHECK-LABEL: @trunc_shl_31_i32_i64_multi_use(
+; CHECK: shl i64 %val, 31
+; CHECK-NOT: shl i32
+; CHECK: trunc i64 %shl to i32
+; CHECK-NOT: shl i32
+define void @trunc_shl_31_i32_i64_multi_use(i64 %val, i32 addrspace(1)* %ptr0, i64 addrspace(1)* %ptr1) {
+  %shl = shl i64 %val, 31
+  %trunc = trunc i64 %shl to i32
+  store volatile i32 %trunc, i32 addrspace(1)* %ptr0
+  store volatile i64 %shl, i64 addrspace(1)* %ptr1
+  ret void
+}