SH = (Op1Opc == ISD::SHL) ? Value : 32 - Value;
}
if (Op1Opc == ISD::AND) {
+ // The AND mask might not be a constant, and we need to make sure that
+ // if we're going to fold the masking with the insert, all bits not
+ // know to be zero in the mask are known to be one.
+ APInt MKZ, MKO;
+ CurDAG->ComputeMaskedBits(Op1.getOperand(1), MKZ, MKO);
+ bool CanFoldMask = InsertMask == MKO.getZExtValue();
+
unsigned SHOpc = Op1.getOperand(0).getOpcode();
- if ((SHOpc == ISD::SHL || SHOpc == ISD::SRL) &&
+ if ((SHOpc == ISD::SHL || SHOpc == ISD::SRL) && CanFoldMask &&
isInt32Immediate(Op1.getOperand(0).getOperand(1), Value)) {
// Note that Value must be in range here (less than 32) because
// otherwise there would not be any bits set in InsertMask.
--- /dev/null
+; RUN: llc -mcpu=pwr7 < %s | FileCheck %s
+target datalayout = "E-m:e-i64:64-n32:64"
+target triple = "powerpc64-unknown-linux-gnu"
+
+define i32 @test1() #0 {
+entry:
+ %conv67.reload = load i32* undef
+ %const = bitcast i32 65535 to i32
+ br label %next
+
+next:
+ %shl161 = shl nuw nsw i32 %conv67.reload, 15
+ %0 = load i8* undef, align 1
+ %conv169 = zext i8 %0 to i32
+ %shl170 = shl nuw nsw i32 %conv169, 7
+ %const_mat = add i32 %const, -32767
+ %shl161.masked = and i32 %shl161, %const_mat
+ %conv174 = or i32 %shl170, %shl161.masked
+ ret i32 %conv174
+
+; CHECK-LABEL: @test1
+; CHECK-NOT: rlwimi 3, {{[0-9]+}}, 15, 0, 16
+; CHECK: blr
+}
+
+define i32 @test2() #0 {
+entry:
+ %conv67.reload = load i32* undef
+ %const = bitcast i32 65535 to i32
+ br label %next
+
+next:
+ %shl161 = shl nuw nsw i32 %conv67.reload, 15
+ %0 = load i8* undef, align 1
+ %conv169 = zext i8 %0 to i32
+ %shl170 = shl nuw nsw i32 %conv169, 7
+ %shl161.masked = and i32 %shl161, 32768
+ %conv174 = or i32 %shl170, %shl161.masked
+ ret i32 %conv174
+
+; CHECK-LABEL: @test2
+; CHECK: slwi 3, {{[0-9]+}}, 7
+; CHECK: rlwimi 3, {{[0-9]+}}, 15, 16, 16
+; CHECK: blr
+}
+
+attributes #0 = { nounwind }
+