llvm/test/Transforms/InstCombine/fpcast.ll
Ahmed Bougacha c0d1ce55ac [IR] fptrunc-of-fptrunc isn't an EliminableCastPair.
Double and single rounding can produce different results.
This is the IR counterpart to r228911.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238531 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-29 00:04:30 +00:00

96 lines
2.4 KiB
LLVM

; Test some floating point casting cases
; RUN: opt < %s -instcombine -S | FileCheck %s
define i8 @test1() {
%x = fptoui float 2.550000e+02 to i8 ; <i8> [#uses=1]
ret i8 %x
; CHECK: ret i8 -1
}
define i8 @test2() {
%x = fptosi float -1.000000e+00 to i8 ; <i8> [#uses=1]
ret i8 %x
; CHECK: ret i8 -1
}
; CHECK: test3
define half @test3(float %a) {
; CHECK: fptrunc
; CHECK: llvm.fabs.f16
%b = call float @llvm.fabs.f32(float %a)
%c = fptrunc float %b to half
ret half %c
}
; CHECK: test4
define half @test4(float %a) {
; CHECK: fptrunc
; CHECK: fsub
%b = fsub float -0.0, %a
%c = fptrunc float %b to half
ret half %c
}
; CHECK: test4-fast
define half @test4-fast(float %a) {
; CHECK: fptrunc
; CHECK: fsub fast
%b = fsub fast float -0.0, %a
%c = fptrunc float %b to half
ret half %c
}
; CHECK: test5
define half @test5(float %a, float %b, float %c) {
; CHECK: fcmp ogt
; CHECK: fptrunc
; CHECK: select
; CHECK: half 0xH3C00
%d = fcmp ogt float %a, %b
%e = select i1 %d, float %c, float 1.0
%f = fptrunc float %e to half
ret half %f
}
declare float @llvm.fabs.f32(float) nounwind readonly
define <1 x float> @test6(<1 x double> %V) {
%frem = frem <1 x double> %V, %V
%trunc = fptrunc <1 x double> %frem to <1 x float>
ret <1 x float> %trunc
; CHECK-LABEL: @test6
; CHECK-NEXT: %[[frem:.*]] = frem <1 x double> %V, %V
; CHECK-NEXT: %[[trunc:.*]] = fptrunc <1 x double> %[[frem]] to <1 x float>
; CHECK-NEXT: ret <1 x float> %trunc
}
define float @test7(double %V) {
%frem = frem double %V, 1.000000e+00
%trunc = fptrunc double %frem to float
ret float %trunc
; CHECK-LABEL: @test7
; CHECK-NEXT: %[[frem:.*]] = frem double %V, 1.000000e+00
; CHECK-NEXT: %[[trunc:.*]] = fptrunc double %frem to float
; CHECK-NEXT: ret float %trunc
}
define float @test8(float %V) {
%fext = fpext float %V to double
%frem = frem double %fext, 1.000000e-01
%trunc = fptrunc double %frem to float
ret float %trunc
; CHECK-LABEL: @test8
; CHECK-NEXT: %[[fext:.*]] = fpext float %V to double
; CHECK-NEXT: %[[frem:.*]] = frem double %fext, 1.000000e-01
; CHECK-NEXT: %[[trunc:.*]] = fptrunc double %frem to float
; CHECK-NEXT: ret float %trunc
}
; CHECK-LABEL: @test_fptrunc_fptrunc
; CHECK-NOT: fptrunc double {{.*}} to half
define half @test_fptrunc_fptrunc(double %V) {
%t1 = fptrunc double %V to float
%t2 = fptrunc float %t1 to half
ret half %t2
}