llvm-6502/test/Transforms/InstCombine/trunc.ll

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; RUN: opt < %s -instcombine -S | FileCheck %s
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
; Instcombine should be able to eliminate all of these ext casts.
declare void @use(i32)
define i64 @test1(i64 %a) {
%b = trunc i64 %a to i32
%c = and i32 %b, 15
%d = zext i32 %c to i64
call void @use(i32 %b)
ret i64 %d
; CHECK: @test1
; CHECK: %d = and i64 %a, 15
; CHECK: ret i64 %d
}
define i64 @test2(i64 %a) {
%b = trunc i64 %a to i32
%c = shl i32 %b, 4
%q = ashr i32 %c, 4
%d = sext i32 %q to i64
call void @use(i32 %b)
ret i64 %d
; CHECK: @test2
; CHECK: shl i64 %a, 36
; CHECK: %d = ashr exact i64 {{.*}}, 36
; CHECK: ret i64 %d
}
define i64 @test3(i64 %a) {
%b = trunc i64 %a to i32
%c = and i32 %b, 8
%d = zext i32 %c to i64
call void @use(i32 %b)
ret i64 %d
; CHECK: @test3
; CHECK: %d = and i64 %a, 8
; CHECK: ret i64 %d
}
define i64 @test4(i64 %a) {
%b = trunc i64 %a to i32
%c = and i32 %b, 8
%x = xor i32 %c, 8
%d = zext i32 %x to i64
call void @use(i32 %b)
ret i64 %d
; CHECK: @test4
; CHECK: = and i64 %a, 8
; CHECK: %d = xor i64 {{.*}}, 8
; CHECK: ret i64 %d
}
define i32 @test5(i32 %A) {
%B = zext i32 %A to i128
%C = lshr i128 %B, 16
%D = trunc i128 %C to i32
ret i32 %D
; CHECK: @test5
; CHECK: %C = lshr i32 %A, 16
; CHECK: ret i32 %C
}
define i32 @test6(i64 %A) {
%B = zext i64 %A to i128
%C = lshr i128 %B, 32
%D = trunc i128 %C to i32
ret i32 %D
; CHECK: @test6
; CHECK: %C = lshr i64 %A, 32
; CHECK: %D = trunc i64 %C to i32
; CHECK: ret i32 %D
}
define i92 @test7(i64 %A) {
%B = zext i64 %A to i128
%C = lshr i128 %B, 32
%D = trunc i128 %C to i92
ret i92 %D
; CHECK: @test7
; CHECK: %B = zext i64 %A to i92
; CHECK: %C = lshr i92 %B, 32
; CHECK: ret i92 %C
}
define i64 @test8(i32 %A, i32 %B) {
%tmp38 = zext i32 %A to i128
%tmp32 = zext i32 %B to i128
%tmp33 = shl i128 %tmp32, 32
%ins35 = or i128 %tmp33, %tmp38
%tmp42 = trunc i128 %ins35 to i64
ret i64 %tmp42
; CHECK: @test8
; CHECK: %tmp38 = zext i32 %A to i64
; CHECK: %tmp32 = zext i32 %B to i64
; CHECK: %tmp33 = shl nuw i64 %tmp32, 32
; CHECK: %ins35 = or i64 %tmp33, %tmp38
; CHECK: ret i64 %ins35
}
implement an instcombine xform that canonicalizes casts outside of and-with-constant operations. This fixes rdar://8808586 which observed that we used to compile: union xy { struct x { _Bool b[15]; } x; __attribute__((packed)) struct y { __attribute__((packed)) unsigned long b0to7; __attribute__((packed)) unsigned int b8to11; __attribute__((packed)) unsigned short b12to13; __attribute__((packed)) unsigned char b14; } y; }; struct x foo(union xy *xy) { return xy->x; } into: _foo: ## @foo movq (%rdi), %rax movabsq $1095216660480, %rcx ## imm = 0xFF00000000 andq %rax, %rcx movabsq $-72057594037927936, %rdx ## imm = 0xFF00000000000000 andq %rax, %rdx movzbl %al, %esi orq %rdx, %rsi movq %rax, %rdx andq $65280, %rdx ## imm = 0xFF00 orq %rsi, %rdx movq %rax, %rsi andq $16711680, %rsi ## imm = 0xFF0000 orq %rdx, %rsi movl %eax, %edx andl $-16777216, %edx ## imm = 0xFFFFFFFFFF000000 orq %rsi, %rdx orq %rcx, %rdx movabsq $280375465082880, %rcx ## imm = 0xFF0000000000 movq %rax, %rsi andq %rcx, %rsi orq %rdx, %rsi movabsq $71776119061217280, %r8 ## imm = 0xFF000000000000 andq %r8, %rax orq %rsi, %rax movzwl 12(%rdi), %edx movzbl 14(%rdi), %esi shlq $16, %rsi orl %edx, %esi movq %rsi, %r9 shlq $32, %r9 movl 8(%rdi), %edx orq %r9, %rdx andq %rdx, %rcx movzbl %sil, %esi shlq $32, %rsi orq %rcx, %rsi movl %edx, %ecx andl $-16777216, %ecx ## imm = 0xFFFFFFFFFF000000 orq %rsi, %rcx movq %rdx, %rsi andq $16711680, %rsi ## imm = 0xFF0000 orq %rcx, %rsi movq %rdx, %rcx andq $65280, %rcx ## imm = 0xFF00 orq %rsi, %rcx movzbl %dl, %esi orq %rcx, %rsi andq %r8, %rdx orq %rsi, %rdx ret We now compile this into: _foo: ## @foo ## BB#0: ## %entry movzwl 12(%rdi), %eax movzbl 14(%rdi), %ecx shlq $16, %rcx orl %eax, %ecx shlq $32, %rcx movl 8(%rdi), %edx orq %rcx, %rdx movq (%rdi), %rax ret A small improvement :-) git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123520 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-15 06:32:33 +00:00
define i8 @test9(i32 %X) {
%Y = and i32 %X, 42
%Z = trunc i32 %Y to i8
ret i8 %Z
; CHECK: @test9
; CHECK: trunc
; CHECK: and
; CHECK: ret
}
; rdar://8808586
define i8 @test10(i32 %X) {
%Y = trunc i32 %X to i8
%Z = and i8 %Y, 42
ret i8 %Z
; CHECK: @test10
; CHECK: trunc
; CHECK: and
; CHECK: ret
}